Sony PSP repair part
New shiny UMD Door trim ring
Quality Stainless steel replacement Trim Ring for your UMD door
With self adhesive backing 
It has a sticky side

Your old scratched trim ring is just stuck to the PSP with adhesive
Use a pin or small screwdriver to lift the old scratched trim ring off the PSP
Once you get it started you can just peel it off and throw it away
Get your new shiny trim ring and just stick it in the place of the old scratched one
This is so quick and easy 
The back of  your PSP will look like new in a few seconds
100% satisfaction guaranteed