Features: brand new and high quality Check that the thread and pitch of the tap and the bolt match. Clear the damaged threads with a standard drill. for Ideal for restoring damaged threads, stripped internal threads and creates a for stronger internal thread in soft metals. Place insert on installation tool and position the adjustable ring so that the insert for tang is centered in the for tang slot. Wind the insert in with a light downward pressure until a half turn below the surface. Never work against the thread direction as the for tang could break. Use the special taps for cutting the holding thread into the cleared hole (recommended to use a suitable cutting oil). Specifications: Material:Metal Type:M5/M6/M8 Length: 10cm/3.94inches Note: Please allow an error of 0-1mm due to manual measurement. Package includes: 25 Pcs Coil Drill Tool Metric Thread Repair Insert Kits in a Set