Experiment 310 - Supermarine Zip Trench

The secret to the future, they say, is hidden in the past. Supermarine F0 Cotton is a 21st century edit to a nearly forgotten World War II fabric. You can think of it as the pinnacle of cotton technology, extremely breathable, highly water resistant and completely windproof. 100% Cotton fibers woven together in a complex weave that swells up and seals when exposed to water. The result is a beautiful cloth that we think is the best rainy day fabric around.

For decades it’s been obscured from the public, kept alive daily by demand from a few Air Force units, Antarctic explorers and funnily enough, bird watchers; all who have different understandings of its unique properties. Supermarine F0 Cotton stays comfortable under pressure and there is none of that sweaty/clammy feeling you get with GoreTex and other synthetic “waterproof-breathable” fabrics. The dense weave combined with the premium fiber results in a fabric that is simultaneously tough and supple and it breaks in beautifully.

Since it requires a very dense weave of the most expensive extra-long-staple cotton fibers on the market, it never quite broke through to the mainstream and with the advent of GoreTex it faded from the general marketplace. Bird watchers still sought it out since it's significantly quieter than the loud synthetic fabrics that took over, while Antarctic teams prized it for its amazing windproof quality. The main customer of the past few decades however has been various Air Forces who understood just how superior a fabric it is, and are willing to pay for it.

Historically this fabric is an updated version of a fabric the British invented in World War II to keep their pilots alive in the North Sea if they happened to get shot down. It was later used by the British Navy, in Antarctic exploration and by Edmond Hillary during the first ascent of Mount Everest. It was even used to make firehoses and eventually found its way into high-end hiking gear.

We source this version of Supermarine F0 Cotton from Switzerland and it differs from the historical British version in two important ways, it is lighter and it is treated with a premium fluorocarbon-free (F0) durable water resistance (DWR). The water resistance in the historical formulation comes from two factors, the denseness of the weave and the fact that cotton fibers swell up when exposed to moisture. Adding the DWR treatment into the mix results in a significantly superior rain repellant and breathable fabric that far outclasses both the synthetic “waterproof-breathable” fabrics of the world and the heavy, clammy Barbour-style waxed cotton. It looks better, wears better and is dramatically more comfortable.