Class L (light) : For any portable corded or cordless drill, with or without percussion # Capacity : 8 mm, 10 mm, 13 mm # Available threaded mountings : 5/16 - 24, 3/8 - 24, 1/2 - 20, 3/8 - 24 ext # Available tapered mountings : J1, J2, J6, B12, B16 # With or without any through hole. Class M (medium) : For any professional portable corded drill, with or without percussion and fixed drill # Capacity : 8 mm, 10 mm, 13 mm, 16 mm # Available threaded mountings : 3/8 - 24, 1/2 - 20, 5/8 - 16, 14 - 200, 18 - 250 # Available tapered mountings : B10, B12, B16, B18, J1, J2, J6, J33 # With or without any through hole. Class H (high) : For any fixed drill # Capacity : 4mm, 6,5 mm, 8 mm, 10 mm, 13 mm, 16 mm, 20 mm, 26 mm # Available tapered mountings : B10, B12, B16, B18, B22, B24, J0, J1, J2, J4,J6, J33 # With or without any through hole.