The image displays components of a thread repair kit, which typically includes a set of tools for fixing damaged or stripped internal screw threads, often used in engine and automotive applications. The kit contains a drill bit (D12.5mm), a counterbore tool (D12.4-D15.5-D18), a tap (M14\*1.5), and a thread insert installation tool (M12\*1.5). The counterbore tool is designed to cut a recess (lip) for the flange of the insert to sit flush with the surface. Threaded inserts, made from materials like stainless steel, create stronger, more durable internal threads compared to the original material. These tools are part of a comprehensive system for reinforcing threads, ensuring a strong, permanent repair when a bolt or stud is frequently installed and removed
eBay