3M™ Dual Lock™ reclosable fastener MP3551/MP3552 is the convenient alternative to traditional fastening methods, such as screws, nuts or bolts. It is designed to deliver a durable, reclosable fastening solution (which can be opened and closed multiple times) that bonds to a variety of substrates including metals and plastics such as acrylics, polycarbonate and ABS. Durable and secure, 3M™ Dual Lock™ Reclosable Fastener MP3551/MP3552 has exceptional strength through its interlocking mushroom shaped heads, providing up to 5X the tensile strength of typical hook and loop products. This trial bag contains type 400 and type 170 stem densities, which can both mate to type 250. We designed this fastener with a white, acrylic, conformable foam tape protected by a removable, film liner. This solid pressure sensitive foam tape features a strong, durable bond that is heat, chemical and UV-resistant. With 3M™ Dual Lock™ reclosable fastener MP3551/MP3552, there is no need for any drilling, screwing or sewing tools which makes for quick installation.