Recoil inserts are the quick and easy way to repair damaged threads or creating stronger original threads in alloys and composite materials in original equipment manufacture.Made from corrosion resistant stainless steel, they create stronger threads in most materials and simplifiy changeover from unified to metric or vice versa.Recoil thread repair kits contain a quality HSS tap, Installation tool, precision stainless steel inserts and instructions. Supplied in a sturdy container.Please note NOT supplied with a tapping drill.ExtensionKit 14.0mm x 1.25Length 1 1/2 X Diameter