This is a sponge PEF sheet (cushion sheet) that can be used for car maintenance, electrical work, and wiring installation. The sponge part is about 1-2mm thick. I bought it in a roll for car DIY projects. I have a lot left over, so I'm selling a set of 10 sheets cut to A4 size. Please note that these are cut by an amateur, so there may be some slight variations. No claims and no returns accepted. If 10 sheets is too many, I can sell a set of 5 sheets for half price (1,000 yen). Please comment if you're interested. Thank you.