Button Compass History: From WWII RAF Escape Kits to Modern Survival EDC
From a downed airman's tunic button to a titanium instrument on your wrist: the button compass is one of the most quietly consequential navigation tools ever made.
Left to right: British RAF escape compass circa 1942, Luftwaffe escape compass circa 1942, current production Francis Barker FB-1605 NATO survival button compass, 22m and 14mm dive rated polyoxymethylene button compaasses. Photo: PDW.
Before GPS, Before Maps on Glass: The Problem of Getting Home
Navigation has always been the first and most critical problem for anyone operating behind enemy lines, lost in the backcountry, or evading capture. A compass gives you the one thing that everything else depends on: a reliable reference. Without north, direction becomes opinion. With it, even the crudest hand-drawn sketch map becomes a workable instrument of return.
The button compass was purpose-built to solve a specific version of this problem: how do you give a soldier or airman a reliable directional reference that cannot be found, confiscated, or detected? The answer, refined under wartime pressure, was to make the compass disappear into the uniform itself. What emerged from that constraint is one of the most elegant pieces of navigation hardware ever produced, and one whose essential design has not changed in eighty years.
MI9 and the Birth of the Escape Compass
The institutional origin of the button compass traces to a British Military Intelligence unit formed on 23 December 1939: MI9, whose mandate was to assist Allied personnel in escaping POW camps and evading capture behind enemy lines. MI9's founding logic was straightforward: the three essentials for any escaper are maps, compasses, and food. The man tasked with solving the compass problem was Christopher Clayton Hutton, a former Royal Flying Corps pilot and intelligence officer described by colleagues as possessing a kind of "tempestuous brilliance."
Hutton's compass work began around the time of the Dunkirk evacuation. He contacted several of Britain's established instrument makers requesting concealable compasses and was turned away each time: the major firms either could not work at the required scale or could not move fast enough. He eventually found his manufacturer in a small London workshop called Blunt Brothers, which had a well-equipped laboratory and the precision machining capability to work at the dimensions Hutton needed. They committed to producing 5,000 small compasses in a week.
Blunt Brothers began with simple bar compasses approximately one inch long with luminous tips, designed to hang from a thread and swing north. From there, the design was reduced further: a smaller prototype with a housing cut from quarter-inch diameter brass tubing, fitted with an outer screw thread, sized to seat inside the reverse of a military uniform button or cap badge. The geometry was determined by the application. The compass had to disappear into the button completely, leaving no trace of what was inside.
Hutton's own assessment of what he and Blunt Brothers had created was characteristically direct: "Every soldier and every airman in future will carry his own passport to freedom on his uniform, in the shape of a compass button."
Between 1942 and 1945, MI9 organized the manufacture and issue of more than 1.3 million round brass compasses, along with 1.6 million maps concealed in purses and pouches, and over 7,000 flying boots that converted into civilian shoes for personnel on the run. By the end of the war, MI9 was credited with helping more than 35,000 Allied personnel escape and return to Allied territory.
The RAF Tunic Button: Concealment as Engineering
At first glance, the RAF escape compass button is unremarkable. It looks exactly like any other button on an aircrew tunic. The external button shell was produced by established military button manufacturers including Firmin of London and Birmingham Buttons Ltd. Inside the recess, the Blunt Brothers compass rotor seated invisibly, the two halves of the assembly separating only when the back was unscrewed.
WWII RAF Tunic Button Escape Compass. Gemini 3, Google, April 6, 2026, https://gemini.google.com
Early war models used a standard right-hand thread. Once the Germans identified the existence of these escape aids, the thread was reversed: a guard trying to unscrew the button by instinct would tighten it instead. That single mechanical inversion is a precise record of how MI9 operated. When a countermeasure was compromised, the assumption behind it was inverted. The thread reversal likely saved lives.
British and Commonwealth buttons screwed open to reveal the rotor compass; American versions used a hinged opening. The same concealment principle extended to collar buttons, fly buttons, shaving brushes, hairbrushes, and lighters. The tunic button remained the most strategically integrated format because it was already present on every uniform, in plain sight, and indistinguishable from its neighbors. When Blunt Brothers' factory was bombed in December 1940, Hutton successfully appealed to Lord Beaverbrook to have repairs made immediately, underscoring how essential the production line had become to the war effort.
The Luftwaffe Version: The Same Problem, a Different Instrument
The Allies were not alone in recognizing the value of a concealable compass. The Luftwaffe developed its own escape compass, and while the operational logic was identical, the execution differed in material and construction. The German version has two glass sides and a circular compass rose with directions marked in black and red. The diameter is nearly the same as the British type at approximately 15.7mm, but the case is brass rather than aluminum, the glass is flat rather than dome-shaped, and the compass rose is printed on an aluminum disc rather than paper.
The Luftwaffe compass reflects the same core insight that MI9 had arrived at independently: a compass small enough to disappear into an airman's kit is a compass that survives capture. Both versions represent the convergence of two opposing air forces on the same problem, arriving at roughly the same answer without knowledge of each other's work.
German Luftwaffe escape compass, circa 1942. Brass case, flat glass, aluminum dial. Note the German cardinal direction markings: O for Ost (East), W for West. Collection: PDW.
Escape and Evasion: What a Button Compass Actually Does
It is worth being precise about the role these instruments were designed to play. A button compass does not replace map-and-compass navigation. It does not give you a bearing to a grid reference, a declination adjustment, or a sighting line to a distant terrain feature. What it gives you is north. That single piece of information, maintained consistently over distance, is enough to keep a man moving in a deliberate direction through terrain where getting turned around means capture or death.
The operational use case was specific: an airman shot down over occupied Europe, stripped of his kit but not yet of his uniform, uses the compass concealed in his button to establish which direction takes him toward neutral territory, a friendly escape line, or cover before daylight. Out of 10,000 RAF prisoners of war, only 30 succeeded in making a full home run back to Allied territory. The odds were severe. But the escape compass was one component in a larger system, and the directional reference it provided was the non-negotiable foundation of any attempt to move with purpose.
MI9 also developed methods to get compasses into camps already in operation. Silk maps of the operational area were hidden in board games alongside compasses made to resemble game pieces. Real currency was concealed among Monopoly play money. The button compass, by contrast, was designed to enter enemy territory with the airman from the start: on his person, in plain sight, and indistinguishable from his uniform.
From Blunt Brothers to Francis Barker: The Design Lineage
The Blunt Brothers compass was defined by a specific and tightly constrained set of design decisions: a small brass housing, a screw-thread body, a rotor needle with luminous north and south indicators, sized to fit inside a standard military button recess. Those parameters were not arbitrary. They were arrived at through the constraint of the application itself: the smallest instrument that could reliably indicate north, concealed inside an object already present on every uniform in the British armed forces.
When the war ended, Blunt Brothers' wartime production closed with it. But the instrument they had produced for Hutton had established a design specification that the British military understood and trusted. The question that followed was not whether to continue producing the button compass, but who should produce it to the same standard in peacetime and to formal military specification.
The answer was Francis Barker and Son, the firm that had been the primary manufacturer of precision compasses for the British military since 1848. Established in Clerkenwell, London, Francis Barker had supplied precision compasses through the Boer War, the First World War, and the Second World War, where their prismatic instruments equipped British Army officers across every theater. They were already the established authority on British military compass manufacture, building to exacting tolerances in brass and glass to specifications set by the War Office.
The postwar Francis Barker button compass carried the Blunt Brothers wartime design directly forward. The same 15mm brass body. The same screw-thread housing geometry that Blunt Brothers had derived from the diameter of a quarter-inch brass tube. The same luminous north and south indicators. Refined now with a jeweled sapphire bearing and a niva-tipped brass pivot for lower friction and greater accuracy across a wide operating temperature range, built not to wartime urgency but to formal NATO specification. The result is the Francis Barker FB-1605, NATO Stock Number 6605 99 522 0223, as specified by the British Army, in-service worldwide and still in current production by Pyser Optics of Edenbridge, Kent, who carry the Francis Barker name today.
The FB-1605 is the Hutton compass, built to last.
Eighty years of the same instrument. The Blunt Brothers wartime design, carried forward by Francis Barker into NATO specification. Collection: PDW.
The SAS, Navigation Selection, and the Button Compass
The connection between the SAS and the button compass runs through two distinct channels, and it is worth keeping them separate.
The first is selection. The Hills Phase of SAS selection lasts four weeks, with candidates required to perform increasingly difficult loaded marches, navigating between checkpoints individually using only a compass and a hand-drawn sketch map. The final test, known as the Long Drag, covers approximately 64 kilometers over the Brecon Beacons, conducted against the clock with a bergen exceeding 55 pounds. Navigation throughout is conducted with a full prismatic compass: the standard British Army instrument, and the tool SAS veterans consistently reference when advising on navigation training. The button compass is not the instrument of record for the Long Drag.
Pen Y Fan, the highest peak in the Brecon Beacons.
Dave.Dunford, Public domain, via Wikimedia Commons
The second channel is combat survival and E&E training, which follows selection. This is where the button compass earns its SAS association. As part of the combat survival phase, candidates undergo escape and evasion exercises where the principles established by MI9 in 1940 remain directly relevant. The FB-1605 carries the informal designation "SAS Survival Button Compass" precisely because of its role in this phase and in operational kit, not in the navigation selection process itself.
The distinction matters. The button compass is a survival instrument, not a primary navigation tool. Its value is in what it gives you when everything else is gone.
The Plastic Button Compass: Accessible, Lightweight, Redundant
The brass military-spec button compass has a civilian counterpart that has become a fixture in survival kits, grab bags, and outdoor gear: the small plastic liquid, oil-filled button compass, available from dozens of other manufacturers, typically ranging from 15mm to 25mm in diameter and priced well under $10.
These compasses are liquid-dampened rather than dry, which gives them faster needle settling and smoother operation. They lack the machined brass construction, jeweled bearings of the FB-1605, but they do typically share luminous markings, however they are not built to a military specification. What they offer is accessibility: a directional reference that can be sewn into a collar, dropped into a survival tin or waterproof match case, attached to a zipper pull, or distributed across multiple kit locations for almost no cost or weight penalty.
PDW waterproof titanium match case (Ti-SST) with strike-anywhere-matches and 14mm actal button compass. Photo: PDW.
For supplementary carry in a vehicle kit, wilderness first-aid pack, or survival tin, a quality plastic button compass from a known manufacturer serves the purpose. The operational logic is the same as it was in 1940: if you have north, you have something to work with. Treat them as an additional layer in a navigation system, not the system itself.
What to Carry and Why
The button compass occupies a specific and irreplaceable position in a navigation kit. It is not a planning tool. It does not give you declination adjustment, map scales, or a sighting mirror. What it gives you is a reliable indication of magnetic north in an instrument that can be carried on your person continuously, without weight penalty or operational footprint, and that will still function after everything else has been lost, confiscated, or destroyed.
For serious carry, the Francis Barker FB-1605 remains the standard. Brass construction, jeweled bearing, luminous markings, and a design lineage running directly from the Blunt Brothers wartime prototypes through to current NATO specification: it is built to survive conditions that would destroy lesser instruments.
For broad coverage across a kit system, a quality plastic button compass costs almost nothing and provides the same cardinal function. Keep one in your vehicle, one in your pack, one in your survival tin. The weight is negligible. The redundancy is not.
The RAF airman who unscrewed his tunic button to orient himself in occupied France in 1942 was doing exactly what the FB-1605 user is doing today: establishing north, then moving. The instrument has evolved. The principle has not changed at all.
PDW: The Button Compass in Titanium Match Case
PDW has incorporated the button compass as a functional component within purpose-built titanium instruments, carrying the same underlying logic of the MI9 escape kit into modern EDC carry. Two pieces in the current lineup make this direct.
The PDW Ti-FST (Fire Support Tool) is a precision-milled aerospace grade G5 titanium billet stash tube built around two core wilderness everyday carry survival needs: fire and navigation. The primary compartment stores fire-making ignitors, including strike-anywhere matches, a ferro rod, and the optional PDW Ti-1HSU. The secondary compartment stores a German-made barrel-style pencil sharpener for producing tinder shavings from field-sourced wood, or pre-made tinder. Built into the cap is an oil-filled, waterproof button compass. The anti-roll hex body and industrial knurled caps, which double as strike surfaces for strike-anywhere matches, reflect the same form-follows-function discipline that defined the original MI9 escape kit: multiple capabilities, minimum profile, no redundant mass. Overall length 4.60 inches, 2.3 oz, corrosion-proof titanium throughout.
PDW Ti-FST. Aerospace grade G5 titanium. Built-in oil-filled button compass in cap. Two watertight compartments for fire-making kit. Anti-roll hex body with knurled striking surfaces.
The PDW Ti-Compass Pendant takes a different approach: a purpose-built wearable compass in a precision-milled 6AL-4V titanium case, designed for fast directional reference on the move. The oil-filled 14mm button compass is depth-rated to 100 meters, with a black dial and glow-in-the-dark markings paired with a GID silicone cushion gasket. The left-right axis cord bore eliminates the need for a counter ring, threading directly with 550 cord, a paracord lanyard, or the optional PDW Ti-Ball Chain. Laser etched on the case back is the Vegvísir, an Icelandic navigational stave traditionally understood to help the bearer find their way through storm and rough conditions. At 21.9mm diameter, 28.7mm height, and 14.2 grams, it perfectly suited for EDC and reaches for use in seconds.
PDW Ti-Compass Pendant. 6AL-4V titanium. 14mm oil-filled button compass. 100M depth rated. GID dial and gasket. Vegvísir etched on back.
Both instruments share the philosophy of the original escape kit: carry the capability before you need it, integrated into what you are already carrying, in a form that survives the conditions that create the need. The button compass inside a WWII RAF tunic button and the button compass inside a PDW titanium capsule or case, are expressions of the same idea, separated by eighty years of materials science.
PDW also offers their own modern, dive rated, 22mm Survival Button Compass as part of the Expedition Watch Band Compass Kit 2.0. For the full navigation category, visit the PDW Compasses collection.
