3M Dual Lock Reclosable Fastener System MP3541/MP3542 Black, 1 in x 5 yd 230.0 mil engaged thickness Black, polypropylene reclosable fastener, rubber based pressure sensitive adhesive 170/400 stems per square inch, black foam adhesive and white polyethylene film liner, bonds well to high density polypropylene and polyethylene, 230 mil engaged thickness. 3MTM Dual LockTM Reclosable Fasteners have been used extensively in transportation, electronics, business equipment, machinery, medical and sign and display markets. When the mushroom-shaped stems interlock, tensile strength is high enough to replace mechanical fasteners in many applications, yet you can readily open and close Dual Lock fasteners hundreds of times. High temperature and solvent resistant. Black, polyproplyene reclosable fastener with rubber based pressure sensitive adhesive and works well on many plastic surfaces.