CRL conical screw anchors 1/4" hole 1" length are made from an extremely durable plastic that has good weatherability and will hold securely in a variety of building substrates. Their shape makes them easy to insert into drilled holes. The wide shoulders will keep them from slipping through the hole. The wide fins will keep them from turning during fastener insertion. Available in 3/16", 1/4" and 5/16" sizes.