N0 (1.524mm) N1 (1.854mm) N2 (2.184mm) N3 (2.515mm) N4 (2.845mm) N5 (3.175mm) N6 (3.505mm) N8 (4.166mm) N10 (4.826mm) N12 (5.486mm) 1/4 (6.35mm) 5/16 (7.938mm) 3/8 (9.525mm) 7/16 (11.113mm) 1/2 (12.70mm) 9/16 (14.288mm) 5/8 (15.875mm) 3/4 (19.050mm) 7/8 (22.225mm) 1 (25.4mm) 1-1/8 (28.575mm) 1-1/4 (31.750mm) 1-1/2 (38.100mm)