Star Insert Bits are made of shock-resistant steel with a hardened core for extra strength and to reduce breakage. These bits have considerably more contact area to engage that results in higher torque capability. Each star insert bit can be used with a hand driver, or with a bit holder in a power drill. The star insert bits can be attached to most drills and electric drivers (or screwdrivers) with a 1/4" Hex Shank. It can fit multiple tip hand drivers and 1/4" hex holders for power driving applications. It can suck the screws easily when used it.