Lenox® 3084712X Hole Saw Extension, 12"For chuck size 1 2" and larger. Fits arbor: 1L, 2L and 3L. Impact hex shank allows for quick changing of the bits. Size: 12" For chuck size 1 2" and larger Fits arbor: 1L, 2L and 3L Also fit snap back 2L Impact hex shank allows for quick changing of the bits WARNING: Some dust created by power sanding sawing grinding drilling and other construction activities contains chemicals known to the State of California to cause cancer birth defects or other