An adaptor to mate with a hand tool such as a folding multipurpose tool to make use of the multipurpose tool as a handle to turn tool bits of various sizes, such as screwdrivers or small socket wrenches. The adaptor includes a drive plate which mates with the hand tool, and a tool bit-engaging member attached to the drive plate and movable angularly between various positions, with a latch to keep the tool bit-engaging member in a selected position. A pair of arms of the drive plate engage the sides of the jaws of one type of multipurpose tool to locate the adaptor as required with respect to the multipurpose tool.