The 1-1/4 in x 9/16 in insulated metal staples secure a large variety of cable types including - NM, BX, MC, AC and UF cables. The insulator is made from a durable polyethylene material which protects cables and helps to prevent arc faults. steel staples offer sharp, burr-free tips which easily bite into wood upon hammering and deter wood from splitting. Do not drive the staple beyond the insulation stops to achieve a clean insertion and secured wiring without damage to cable or wood. 9/16 in staples secure 3 conductor NO 14, NO 12 and NO 10 non-metallic BX, MC, AC and UF cable.