Read enough LED mask reviews and you'll find the same sentence over and over, in slightly different words: it hurts my nose.
It's a strange thing for an expensive product to get wrong, and it happens because most masks are designed to one shape and sold to every face.
Why it happens
Rigid masks are moulded to an average. If your face is narrower, wider, or your nose bridge sits differently to whatever average the mould was built around, the pressure lands in one spot instead of spreading across the cheekbones.
Ten minutes of light pressure on the bridge of your nose is fine. Ten minutes of a hard plastic edge is not, and you won't do it a second time.
The six things to check
1. Rigid or flexible. Silicone masks conform to the face and forgive a lot of variation. Rigid ones deliver light more evenly but fit fewer faces. Neither is simply better.
2. The nose bridge. Look for a cut-out or a soft section. A hard continuous edge across the bridge is the single most common source of the complaint.
3. Strap adjustability. Two adjustment points beat one. An elastic band with no adjustment at all is a red flag on anything premium.
4. Weight. Worth checking the spec. Anything much over about 350 grams starts to pull, particularly if you're lying down.
5. Eye coverage. Some masks have cut-outs, some have opaque sections, some expect you to close your eyes. Any of those is fine. What you want to avoid is bright light directly on closed eyelids for ten minutes with nothing between.
6. Return policy. The honest one. You cannot tell whether a mask fits your face from a photograph, so the only real protection is being able to send it back.
The question worth asking a brand
Ask whether they'll take it back if it doesn't fit comfortably. Not whether it works. Whether it fits.
A brand that gets defensive about that question is telling you they've had the conversation before.
Where we sit
We don't sell a mask. If we ever do, fit is the first test it has to pass, before light output — a strap that won't tighten enough for a smaller face is reason enough to say no. We'd rather say that publicly than pretend the category doesn't have this problem.
General information, not personal advice.