3 Count Heavy Duty Roofing Hook Blades 11-939 11-939 Features: -Roofing hook blades.-Cuts shingles, felt paper and similar materials.-75 pct stronger.-3 per card. Features Edge is engineered to withstand the rigors of cutting today?s heavy and thick roofing materials 75% stronger than Stanley?s 11-983 Hook Blade, resulting in fewer blade changes Cuts roofing shingles, felt paper, Tyvek, foam board, insulation, shingles and other building materials Designed for use in fixed blade knives only ?ROOF? call-out is laser etched on blade to help prevent accidental mixing with standard blades USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.