Covington automatic vibrating lap 12" model #394AVL is designed to abrade and polish automatically. The inertia of the heavy rock slab holds it relatively still while the lap pan vibrates underneath. This action replaces the circular rotation used by conventional lapping machines. The new design and groved plate give faster cutting. Bumper ring prevents gemstone damage. Pad insert enables work piece to be polished in the same pan. One thumb screw releases pan for easy cleaning. Complete with 110 v, 60 hz motor, polish pad, bumper ring, instructions and guarantee. The Covington lap pan size is 12", box dimension 14" x 14" x 10", and shipping weight is 25 pounds. FOB Redlands, CA