As the name suggests - the SuperGrip Jaws are designed for holding long work pieces securely. The small jaws are 35mm and the large jaws are 38mm deep with a long dovetail that securely engages and holds the work piece in place when turning a long distance from the headstock. Both will hold work pieces up to 500mm (20in) from the jaws in two different size ranges.
The small also has a special cut-away in the jaw to more securely hold square stock in the chuck.
Small Jaw Capacity
Jaw Travel Expanding - 37 - 77mm
Jaw Travel Contracting - 29 - 59mm
Large Jaw Capacity
Jaw Travel Expanding - 80 - 110mm
Jaw Travel Contracting - 60 - 93mm