Bosch 1639K Rotary Saw Kit Includes 1/8" and 1/4" collets, 9 assorted bits, open end wrench, depth guide, cutting guide, and carrying case Durable non-marring base-for smooth, consistent cutting Spindle lock button for easy bit changes Quick clamp removeable depth guide; attaches, adjusts, and detaches in seconds 2 speed bump off switch for ease of operation.