Knitter's Pride Knit Blockers are a great new way to block knitting projects! They're so easy to use, they'll really speed up the blocking process. The novel design helps maintain even tension across the width of the blocking pins - working best on straight edges. Anchor holes in each blocker allow you to attach string along large sections which can be pulled and pinned to maintain consistent tension. The Knit Blockers are made using strong plastic with sharp, sturdy & rust resistant stainless steel pins in two sizes in order to handle different shapes when blocking.