3M 7000049438 Dual Lock Fastener SJ3871 Black 1in X 45yd

Product Description

The 3M 7000049438 is a Dual Lock reclosable fastener in the SJ3871 series, designed for secure, tool-free mechanical attachment across a wide range of surfaces. The fastener strip features 400 mushroom-shaped stems per square inch of black polypropylene, backed by a modified acrylic pressure-sensitive adhesive for direct surface bonding. Engaged thickness measures 0.24 inches, providing a low-profile yet firm closure. The system is rated for a closure life of 1,000 cycles and offers temperature resistance up to 180 degrees F, making it suitable for both indoor and outdoor installations where repeated access is required.

This fastener is commonly used in commercial, industrial, and light trade applications where panels, covers, or components need to be removed and reinstalled regularly without fasteners or tools. Typical scenarios include securing electrical enclosure covers, HVAC access panels, ductwork insulation blankets, and equipment housings. The adhesive is formulated to bond to many plastics including polyethylene, acrylic, and polycarbonate, as well as ABS, powder-coated surfaces, and medium to low surface energy materials.

Key Features

• 400 stems per square inch for consistent, repeatable closure strength
• Modified acrylic adhesive bonds directly to plastic, coated, and low surface energy substrates
• Rated for 1,000 open-and-close cycles for long-term reliability
• Temperature resistance up to 180 degrees F supports medium-temperature environments
• Black polypropylene construction resists moisture for indoor and outdoor use
• 1-inch width by 45-yard roll length for high-volume or large-area applications

Compatibility

Designed for bonding to many plastics including polyethylene, acrylic, polycarbonate, and ABS, as well as powder-coated paints and medium to low surface energy materials in indoor and outdoor environments.

Installation Notes

Surface preparation is critical for adhesive performance — clean and dry the substrate thoroughly before applying the fastener strip, removing any oils, dust, or coatings that could reduce bond strength. Apply firm pressure along the full length of the strip after placement to ensure proper adhesive contact. Allow the adhesive to dwell for the manufacturer-recommended time before loading the joint. This product is not intended for use on high-temperature surfaces exceeding 180 degrees F.

Technical Specifications

• Series: SJ3871
• Stem Density: 400 stems per square inch
• Engaged Thickness: 0.24 inches
• Closure Life: 1,000 cycles
• Temperature Resistance: 180 degrees F
• Width: 1 inch
• Length: 45 yards per roll
• Color: Black
• Material: Polypropylene with modified acrylic adhesive
• Application Environment: Indoor and outdoor
• Weight: 5 pounds
• Unit of Measure: Roll

Standard Information

• Brand: 3M
• Manufacturer Part Number: 7000049438