Dormer Dienuts are used to reclaim worn or damaged threads in most materials. Metric Coarse Dienuts. Application: For reclamation of screw threads. Also available in MF UNC G(BSPF) thread forms. Tolerance: 6g.Chamfer Lead: Two Threads.Surface treatment: Bright.Material: HSS - High Speed Steel. BS1127:1950Size: 6mm x 1.00.PTDDORF302M6