These Big Easy Jaws™ are perfect for the inside of bowls, platter and hollow forms. They include 8 urethane Easy Grippers™ that help to protect your work, ideal for when your finish has already been applied and you are working on the base of your piece. Swapping your jaws is easy, thanks to Snap-Lock Technology; use the ball and hex key, press down on the keeper latch, slide your jaws on, listen to the snap and the jaw is then locked into position within 30 seconds. The 12" Big Easy Jaws have a maximum grip diameter of 10" and the maximum expanding dimension is 11.1/2". When jaws are fully closed, the outer diameter is 10.3/4". Fully open, the outer diameter is 12". Please ensure your lathe has a minimum swing of 12" when using these jaws. The 16" Big Easy Jaws have maximum grip diameter of 14" and the maximum expanding dimension in 15.1/2". When jaws are fully closed, the outer diameter is 14.3/4". Fully open, the outer diameter is 16". Please ensure your lathe has a minimum swing of 16" when using these jaws. Both supplied with 4 base jaws, 4 jaw plates, 8 dovetail grippers and 1 5/32" T-handle hex wrench. Compatible with the Easy Chuck only.-bg