Dual Lock 250 Reclosable Fastener 3M SJ3550 is a general-purpose black reclosable fastener with 250 stems per square inch, an engaged thickness of 0.23 inches and a closure life of 1,000. This black fastener has mushroom-shaped stems on a polypropylene carrier which is coated with a white, general-purpose acrylic pressure-sensitive adhesive. Type 250 stem density fasteners can mate to type 170, 250 or 400 fasteners (the higher the combined number the greater the closure strength). Mushroom-shaped stems on one side of the fastener interlock with identically shaped stems on the other side for 5X greater closure strength than hook and loop.
Dual lock type 250 fasteners are designed to bond to metals, glass, and medium-to-high surface energy plastics and paint. They can replace conventional fasteners such as screws, clips, rivets, snaps, hook and loop and bolts in many applications where access or repositioning is needed. Used to attach doors, access panels, signs, cushions, wall headliners, display components, city bus light fixtures, ceiling attachment, privacy curtain rails, sunroof trims, and wall panels. Also for POP (point of purchase), trade show exhibition and electronics, and for attaching E-ZPass tags to car windshields.
Dual lock only has one type of side; unlike products where there is a separate hook and a loop side; so rolls are typically cut in half and then mated or connected so a 10-foot roll would be used as two 5-foot strips. Made in the U.S.
Technical Information- Backing/Carrier: polypropylene
- Adhesive: acrylic (300 LSE)
- Release Liner: clear polyolefin film
- Thickness: 140 mils (carrier, adhesive) 4 mils (liner)
- Service/Operating Temperature: up to 200F
- Engaged Thickness: 230 mils
- Pins: 250 per square inch
We also offer alternative for 3M SJ 3551.