Class M (medium) :
For any corded or fixed drill, without percussion.
# Capacity : 6,5 mm, 8 mm, 10 mm, 13 mm, 16 mm
# metal sleeve
# Available threaded mountings : 3/8 - 24, 1/2 - 20, 5/8 - 16
# Available tapered mountings : J1, J2, J3, J6, J33, B10, B12, B16, B18

Class H (high) :
For any fixed drill or machine tool.
# Capacity : 8 mm, 10 mm, 13 mm, 16 mm
# metal sleeve
# Available tapered mountings : J1, J2, J6, J33, B10, B12, B16, B18