These are sticky‑back nylon hook‑and‑loop fastener strips from VELCRO® Brand, sized at 3‑1/2 inches long and ¾ inch wide, and sold in a convenient 4‑pack. Each strip features a peel‑and‑stick adhesive backing, so you can easily attach them to most smooth and clean surfaces such as finished wood, glass, tile, metal, or plastic — no tools required.