- Interlocking mushroom-shaped stems snap together to form a strong, fast and easy attachment
- Die-cut base incorporates counter-sunk holes for attachment using screws or rivets
- Secures with an audible snap for closure verification
- Resistant to high temperature and solvents, ideal for automotive applications
- Strong holding power reduces the rattling and vibration of components
- Does not require any special tools or processing equipment
- Mates with other stem densities to achieve a variety of engagement and disengagement forces
3M™ Dual Lock™ Reclosable Fastener SJ3252 Die-Cut Piece Part is a 38mm square reclosable fastener with a rigid polypropylene backing and two holes for screws or rivets. It has a stem density of 400 stems per square inch. The mushroom-shaped stems interlock to supply very high tensile strength and replace mechanical fasteners in many applications.
Mushroomshaped polyolefin stems that snap together
Additional Features include:
How It Works
- Quick attachment to second fastener with no drilling or additional tools required
- Hidden attachment avoids unsightly mechanical fasteners on the show surface
- High temperature and solvent resistance
- Mushroom heads that allow flexibility in alignment for easy attachment of components
- Can be used to attach components before they enter the final assembly plant, thus helping to reduce the number of parts and the length of assembly time
- Combinations of stem densities and the engaged area provide adjustable and proportional engagement and disengagement forces
- An audible snap confirms that the part is correctly installed with minimal insertion force required by the assembly worker
This die-cut fastener is designed to be screwed or riveted to a base where attachment is desired. It is supplied with a counter sunk hole for easy attachment using pan-head screws, pop-in rivets, or an ultrasonically stacked post. The head of the screw or rivet must be recessed below the bottom of the mushroom stems to allow proper engagement of the mushroom heads.
The fastener has a rigid polypropylene backing that holds firm to the base through many openings and closings. The die-cut piece can be snapped to a second Dual Lock fastener attached to another part forming a secure, dependable and repeatable attachment.
When two pieces of 3M™ Dual Lock™ Reclosable Fasteners are pressed together, 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.
Alignment and re-alignment are easy and no special tools are required. This means that these fasteners can be used to attach components before they enter the final assembly plant, thus helping to reduce the number of parts and the length of assembly time.
400 stems/inch2 (62 stems/cm2)
3M™ Dual Lock™ Reclosable Fasteners allow customers to combine different stem densities and engaged areas to create adjustable and proportional engagement and disengagement forces to suit their application. Dual Lock fasteners are offered in three different densities (stems per square inch): 170, 250, and 400. Our Dual Lock fastener SJ3252 has 400 stems per square inch (25mm), offering the tightest hold, and can be mated to Type 170 or 250. It should not be mated with another Type 400 fastener because the hold would be so tight that detachment would likely result in damage to the parts.
3M™ Dual Lock™ Reclosable Fasteners can replace conventional mechanical fasteners in a wide range of assembly and attachment applications where reclosability or serviceability is desired. Dual Lock fasteners are used primarily to secure rigid and semi-rigid surfaces such as trim or door panels, instrument panel bezels, headliners, and other automotive interior and exterior trim. Some examples of applications include:
3M Science Delivers Closures You Can Count On
- Trunk liners
- Door panels
- Toll transponders
- Vehicle headliners
- Interior lighting
- Window and door trim
- Vibration and sound dampening control
- CHMSL Center Height Mount Stop Lamp cover plates
- Center console flanges
3M™ Dual Lock™ Reclosable Fasteners are ideal for many applications where a high strength, reclosable fastening system is required. 3M engineers have uniquely combined physics and materials science to bring the automotive industry reliable fasteners that supply high performance even after exposure to ultraviolet radiation, high moisture levels and wide temperature ranges. For applications that require a die-cut piece and multiple closures, look no further than the long-lasting durability of our 3M™ Dual Lock™ Reclosable Fastener SJ3252 Die-Cut Piece Part. It is yet another outstanding example of how 3M technologies advance operations in the automotive industry, providing both ease of use and superior results.
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