Three things at once, for fifteen minutes: warmth, red and near-infrared light, and vibration. The warmth comes from the light panel itself rather than a separate heating element, so heat and light go up and down together — you can't turn one up without the other. It is not a compression device and there is no pump.

It won't change what's bone on bone. It works on the stiffness and the muscle guarding around the joint, which is a different problem from the joint surface itself — and for a lot of people it's the part that decides how the night goes. Being bone on bone and having a worse night than you need to have are two separate things.

The vibration and the warmth you feel in the first session. The light you won't feel at all, ever — if it does anything it does it cumulatively. Trials of red and near-infrared light on knees generally run three to five sessions a week for four to eight weeks before measuring anything, so judge it on your nights across two or three weeks, not on night one.

It opens out to about 90 cm across and closes with three adjustable straps — top, middle and bottom. That's generous for an adult knee, so most people have overlap to spare rather than a struggle to close it. One size; the straps are what you adjust.

Fifteen minutes, then it shuts off on its own. The timer also offers 30 and 45 minutes — don't use them. The manufacturer's own instruction is not to use it on the skin for longer than fifteen minutes, and the reason given is burns. Longer isn't better here.

One at a time, yes. Most people with both going order two rather than sitting through two sessions back to back.

Then this probably isn't for you, and we'd rather say so now than at day 60. Warmth suits the stiff, achy, seizes-up-when-you-sit-still knee. If yours is the kind that wants ice, that's a real pattern and this is the wrong tool for it.

No. One payment, one device, nothing to reorder and nothing to cancel. There are no pads, gels or refills.

Ninety days from the day it arrives — not the day you ordered, so transit time doesn't come out of your trial. If it hasn't helped, email info@wyntrol.com before the ninety days are up and we'll refund you in full. No restocking fee, no form to fill in, and you don't have to give a reason. Separately, the hardware is covered for two years.

Orders are processed within 1–2 business days. Delivery to the United States is typically 8–16 business days from dispatch — these are estimates, not promises. All taxes and duties are included in the price at checkout: there is nothing further to pay on delivery and no customs bill at the door. You'll get a tracking link by email as soon as it ships.

They may well be right, and this isn't sold against a new knee. Nobody here is a clinician and nothing on this site is medical advice. This is for the part you're living through in the meantime, and it sits alongside whatever your doctor has told you — never instead of it.