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. BS1127:1950 Size: 6mm x 1.00. DORF302M6