3Mô Hook Fastener SJ3402 is our general purpose hook fastener that features no adhesive or liner. It is an attachment alternative to a wide variety of closures, including zippers, screws, snaps, hooks and more. This fastener is covered with flexible J-shaped hooks, about 300 hooks per square inch (46 hooks/square cm.), which protrude up from a woven backing. Commonly paired with 3Mô Loop Fastener SJ3401, this hook fastener can also engage with other 3Mô Loop Fasteners. To ensure stability and flatness, both the hook and the corresponding loop are preshrunk.