3M™ Dual Lock™ Reclosable Fastener SJ3440, Black, 1/2 in x 50 yd, Type 250, 4 Roll/Case

Unlock Simplicity

Durable and secure, 3M™ Dual Lock™ Reclosable Fastener SJ3440 has exceptional strength through its interlocking mushroom-shaped heads (250 stem density per square inch). With 3M™ Dual Lock™ Reclosable Fastener SJ3440, there is no need for any drilling or screwing. This fastener is most commonly attached by applying hot melt, epoxy or liquid adhesive.

Recommended Applications:

Alternative to pressure sensitive adhesives

Design Flexibility

3M™ Dual Lock™ Reclosable Fastener SJ3440 consists of interlocking mushroom-shaped heads that easily slide over each other, allowing for positioning of parts before being snapped together. This fastening process creates a durable attachment and provides fast product assembly with great design flexibility. Reclosable fasteners can also engage with different stem densities for varying levels of strength and system performance.

3M™ Dual Lock™ Reclosable Fasteners sound an audible snap when secure, which verifies closure of the attachment. To disengage, simply peel the pieces apart by hand. These fasteners maintain their strength throughout multiple attachments and detachments. A lightweight alternative to metal fasteners, this product remains hidden beneath surfaces and does not interfere with the integrity of your material—providing aesthetic improvements and design flexibility.

Hundreds of Reattachments in a Snap

When two pieces of 3M™ Dual Lock™ Reclosable Fasteners mate, the stems flex and the mushroom heads slide past each other. After passing the opposing mating piece, the stems snap back into their original position and the opposing mushroom heads interlock. These fasteners can provide high tensile strength but can be opened by simply cleaving or peeling open the closure. This product is well suited for many indoor applications where a good performance, high strength, reclosable fastening system is required.

Delivers Long-Lasting Performance

Not all design requirements are easily satisfied, but you can simplify your attachments. When you need a strong, reliable, yet removable closure, 3M™ Dual Lock™ Reclosable Fasteners are the easy alternative to traditional fastening methods such as screws, nuts or bolts.

• Black, interlocking mushroom-shaped heads (250 stem density per square inch) provide strong, reliable and durable fastening that can be opened and closed multiple times
• Mates with Type 170, Type 250 or Type 400 stem densities to provide different strength combinations
• Non-adhesive back for attachment with hot melt, epoxy or liquid adhesives
• Strong fastener secures with an audible snap, verifying closure
• An alternative to screws and bolts, this hidden fastener provides a snug fit and smooth aesthetic appearance
• Features good temperature resistance of 220°F (104°C), though temperature resistance may change based on adhesive used
• Suited for indoor or outdoor use