SINWEEK Tri-Folding Mattress Foam Topper 38 x 75 x 4 Inch Folding Pad with Removable Cover & Waterproof Lining

Can you sleep on it right away?

The listing says it's certipur certified but the company is not listed on the certipur site. can the company please confirm certification?

Does this have a nonslip bottom?

can you feel the seams?