3M™ Hook Fastener SJ3506 is one part of a two-part fastener solution designed to provide great design flexibility and fast product assembly. With its acrylic-based pressure sensitive adhesive backing, this low-profile fastener allows for easy and convenient attachment for lightweight applications. - 3M hook fastener SJ3506 is one part of a durable, two-part fastener solution that offers design flexibility, fast product assembly, smooth and clean exterior surfaces and improved product performance. Using a pressure sensitive adhesive eliminates or reduces the need for sewing, solvent activation, dielectric or ultrasonic bonding or bulk adhesive bonding.