You know the hour. Somewhere around three you surface, and the sheet is stuck to the backs of your legs. You kick it off, you get cold, you pull it back, and twenty minutes later you are damp again. It is not the room temperature — you have tried the window. It is the sheet. Smooth cotton percale and anything with a sateen finish lie flat against your skin, and once there is a film of moisture between the two, that contact is total.

Slub™ is woven to do the opposite. Flax is spun with its slubs left in — the thick and thin irregularities that a cotton mill would comb out — and the weave is left open. The result is a surface of thousands of tiny ridges, so the fabric touches you in points rather than across a plane. Air moves in the gaps. The flax fibre itself is hollow, wicks roughly a fifth of its own weight in moisture, and releases it fast, so sweat is pulled off the skin and gone rather than held against it. That is the whole mechanism, and it is structural — there is no finish on it to wash out.

It has already been stonewashed, which is the difference between linen you like and linen you tolerate. New unwashed flax is stiff and scratchy and takes a season of laundering to break in. This has had that season done for it: tumbled with stone before it ships, so the fibres are already broken down and it comes out of the bag soft, matte and heavy in the hand. It keeps softening — flax is one of the few fibres that genuinely improves with washing rather than pilling and thinning.

This is the white. Not the blue-white of a hotel sheet — there are no optical brighteners in it, so it reads as a soft warm white that sits quietly against oak, plaster and oatmeal rather than shouting over them. It will crease, and it is supposed to; a linen sheet that lies perfectly flat is a linen sheet with something sprayed on it. Four bed sizes, one flat sheet per pack, plain double-turned hem all round.

Machine wash warm at 40°C on a normal cycle, on its own or with other white linen, and do not overload the drum — flax needs room to move to keep softening. Use a mild liquid detergent and no more than the dose; powder grains lodge in the weave and dull it. Skip fabric softener entirely, and skip chlorine bleach: softener coats the fibre and undoes the wicking you paid for, and bleach weakens flax and will eventually yellow it. If it ever needs brightening, an oxygen-based whitener used sparingly is safer than chlorine. Tumble dry low and take it out slightly damp, then put it straight on the bed — that is the best press it will ever get. Line drying works too, and sunlight keeps the white clean. If you must iron, do it damp on a medium steam setting, though most people stop after the first month. It will crease. That is what it is meant to do.

100% French flax linen, stonewashed, in a soft warm white with no optical brighteners added. Plain weave with the slub left in, plain double-turned hem on all four sides, no elastic and no fitted corners. Sold as one flat sheet per pack; pillowcases and duvet covers are not included. Sizes are the finished sheet, not the mattress: 150 × 230 cm for a single, 180 × 220 cm for a double, 220 × 240 cm for a king and 240 × 260 cm for a super king. Because it is washed rather than pressed, small variations in shade, slub density and hem length between pieces are normal.