You pull a sweater out in the first cold week and something about it reads old. Nothing is torn. The color looks dulled, the surface looks fogged, and you put it back and reach for something else. Get it into daylight and look close. The knit underneath is fine. On top of it sits a layer of tiny balls. Those are pills.

Pills are the sweater's own fiber. Friction makes them: the sides where your arms swing, the strip where a bag strap rides. Short fibers work loose, tangle into a knot, and stay anchored by a strand or two. Washing does not take them off. Washing makes more. So a sweater can be sound and still look used up.

A blade spins behind a screen. You rest the screen on the cloth. Only what stands proud of the surface pushes through the holes, and that is what the blade meets. It cuts the ball off flat. The weave underneath never reaches the edge. What comes off collects in a cup you empty.

The screen is why this beats what people reach for first. Tape lifts lint that is already loose. A pill is not loose. It is attached. A disposable razor will cut one, but there is nothing between the blade and the knit, so it takes the pill and sometimes a thread of the weave with it.

Here is what it will not do. It takes the pills off and nothing else. A thinned elbow, a cuff that has lost its spring, a hole, a washed out color: all of it is still there when you finish. If the sweater is genuinely worn out, you get a clean worn out sweater.

Go slow on loose and chunky knits. A slack weave can be drawn up into the screen if you lean on it. Light pressure, keep it moving, and empty the cup before it packs full.

Treat it as maintenance, not repair. The pills come back, because what makes them is you wearing the thing. But on a black sweater the change is not subtle. It stops looking dusty and goes back to looking black.