LENOX Tools Snap-Back Arbor Extension, 12-inch, 1L / 2L / 3L (1852048). The snap-back quick-change lets you engage and disengage extension from hole saw quickly and easily with just one hand. No tools necessary. The patented jaw design holds bits securely on ball detent bits; no threads to strip. Magnets in the connector provide additional holding power. A carbon steel collar and shaft provide durability and extended tool life. Requires no adapter. The arbor threads directly into all hole saws. Works with 1/4-inch arbors and insert bits. Fits 1L, 2L, and 3L Standard Arbors and 2L Snap-Back arbors.