my Band 2 has some scratches in metal plate ( the plate where is UV sensor, i've attached a photo).
Someone knows a product that removes these scratches?
I think the big issue would be that any product that will buff out the scratches might damage the UV sensor. The problem with stainless steal is that it is relatively soft on the Mohs Scale of mineral hardness. Your best bet would probably be to take it to a jeweler to buff out the scratches, but it will just get scratched again.
I used 0000 steel wool on a SS sink, and it remove the scratches quite well. For a mirror finish; you could use 8000grit 3m wet/dry polishing paper (EM2705). DO NOT apply to/on/over/near the sensor.
Remover the large scratch with the 0000 steel wool, than work down to the 8000 grit paper.