Dual Lock Reclosable Fastening Systems offer closure alternatives to zippers, screws, snaps, and more.
The interlocking mushroom head closure system is 5 times stronger than hook and loop.
Use this Dual Lock Fastener for attaching removable cabinet doors, access panels, signs, furniture cushions, headliners, and display components, etc.
This 3540 Series/Type 250 fastener has a synthetic rubber based adhesive on the back of a black polypropylene reclosable fastener with 250 mushroom stems per square inch.
The rubber adhesive is suitable for bonding to many high and low surface energy (difficult to adhere to) materials including powder coated paints, high surface energy plastics (acrylic, polycarbonate and ABS), and low surface energy plastics (polypropylene and polyethylene).
At 250 stems per square inch, it forms a moderately strong bond to itself.
(See the Related Products entries, below, for more details about closure strengths.)
• Approximately five times stronger in tensile than typical hook-and-loop fasteners
• No dirt catching fuzz, like hook and loop closure systems
• Can be opened and closed 1,000 times before losing 50% of its original strength
• Can be opened and closed hundreds of times
• For indoor use
• Low temperature resistance (to 120°F)
• Engaged thickness is just under 1/4"
The Dual Lock system consists of continuous strips of plastic mushrooms protruding up from a backing which is typically coated with a high strength pressure sensitive adhesive covered with a peel-off liner.
When 2 strips are pressed together, the mushroom heads interlock, forming a releasable mechanical bond.
There are three Types of these fasteners 170, 250, and 400 — referring to the approximate number of mushrooms per square inch.
They can be mated in the following combinations of increasing closure strength —
Type 170 to Type 250
Type 250 to Type 250
Type 170 to Type 400
Type 250 to Type 400
(Type 170 will not stick to itself, and Type 400 to Type 400 is essentially a permanent bond.)
The "release strength" is a function of the Type(s) selected as well as the surface area of the fastener.
Note that unlike Hook & Loop Fastenings, there is no "male" or "female" side.
Both "sides" are identical - so you only buy one strip; but as noted above, different Types can be mixed to achieve the correct release strength.