3M™ Dual Lock™ Reclosable Fastener SJ3704, Pop-in Piece Part, Black, Stem Density 250, 26 mm x 26 mm, 550 Each/Case

3M™ Dual Lock™ Reclosable Fastener SJ3704 is a black, polypropylene reclosable fastener with a pop-in rectangular base and a square top. It has a stem density of 250 stems per square inch. Unlike traditional fasteners, this product does not require pressure sensitive adhesive for attachment. It comes with a variety of bases that can be inserted into holes of precise dimensions. Installation is easy and does not require any special equipment or skills.

This fastener is designed to overcome the alignment and installation problems often encountered with screws and hidden fasteners. It offers a simple installation process without the need for special tools. 3M™ Dual Lock™ Reclosable Fasteners are blind fasteners that provide a positive-locking mechanism. They are specifically designed for attaching automotive trim components. The fasteners feature mushroom-shaped polyolefin stems that snap together, creating a high tensile closure. They are primarily used to secure rigid and semi-rigid surfaces such as trim or door panels, instrument panel bezels, headliners, and other automotive interior and exterior trim.

How It Works
This pop-in fastener is inserted into a slot of specific dimensions where attachment is desired. The polypropylene rectangular base grips the inside of the hole securely. The fastener can then be mated and engaged to a second Dual Lock fastener attached to a piece of trim or another part, firmly securing the parts together.

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 provide high tensile strength but can be easily opened by cleaving or peeling open the closure.

Alignment and re-alignment are effortless, and no special tools are required. This makes them suitable for attaching components before they enter the final assembly plant, reducing the number of parts and assembly time.

Stem Densities
3M™ Dual Lock™ Reclosable Fasteners are available in three different stem densities: 170, 250, and 400 stems per square inch. The stem density, combined with the engaged area, provides adjustable and proportional engagement and disengagement force to meet specific application needs. Dual Lock fastener SJ3704 has 250 stems per square inch, offering a secure hold when mated to another 250 stem density part or a Type 170 or 400 part.

Applications
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. They are primarily used 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:

• Vehicle headliners
• Attaching accessories and equipment
• Attaching window and door trim panels
• Vibration and sound damping control
• CHMSL cover plates
• Center console flanges
• Interior trim
• Sunroof rings