This instrument is an Orthopedic Bone Tap / Screwdriver with a T-Handle, commonly used in orthopedic, spinal, and veterinary surgeries for bone fixation.

A T-handle provides the leverage needed to drive screws, taps, and reamers, particularly in dense bone. Taps with T-handles are used to cut threads in bone for screw placement, and these instruments are typically available in specific sizes corresponding to screw diameters, such as 3.5mm, 4.0mm, 4.5mm, and 6.5mm.