#1 Phillips ® Apex® bits, 1/4'' hex power drive shank, 2 3/4'' overall length, ACR ® both ways. Phillips ® bits from Apex® Fastener Tools can be used for driving screws and fasteners with hand tools, corded or cordless power tools, and pneumatic tools. Phillips ® bits from Apex® Fastener Tools formally Cooper Tools are popular throughout the aviation industry as well as automotive, heavy industry or anywhere quality tooling products are required. Apex® Phillips ® bits are known worldwide for their quality construction and durability in demanding conditions.