Knitter s Pride Knit Blockers and Pin Kit-These easy-to-handle blockers substantially speeds up blocking on all types of projects. The design helps maintain even tension across the width of the blocking pins. Ideal for blocking straight edges like sweaters, shawls, and scarves. Anchor holes in each blocker allows the user to attach string along large sections which can be pulled and pinned to maintain constant tension. Made with tough plastic embedded with sharp, sturdy and rust resistant stainless steel pins.