Average but for 11 euros including shipping and cash on delivery, don't expect anything fantastic. As filters, they are okay, but the fit is not good because the plastic around the nose is hard and not soft like in diving masks, so it uses a "sock" that can be removed and washed, but obviously it is also permeable, blocking the filters. The elastic band it has is terrible and will not last, while the tightening strap to fit on the head is laughable and constantly comes off, so I tied a knot where it was stretched enough to hold, and for as long as it lasts. The filters do not seem to be detachable to change, but I will find out and come back once it's time to change them or throw it away if they don't change. Cheap Chinese product to use 2-3 times, and that's it. You get what you pay for.