Introducing the Astro Tool 94409TS 9-Piece 3/8" Drive Nano Impact Triple Square Bit Sockets. Like our popular Torx and Hex bit sockets, these are extra low profile at 1-1/8" long, designed 26% shorter than others allowing for more access, direct transfer of impacts and increased durability Just add an extension for longer reach. These sockets are lifetime warranty forged from S2 alloy uniquely treated to provide superior resistance to twisting and chipping compared to CR-V, CR-MO and even other S2 sets. Larger sizes feature tamper proof design. This set includes the following: one aluminum socket holder rail and impact bit sockets in sizes M4, M5, M6, M8, M10, M12, MT14, MT16, MT18.