Now you can machine bigger box joints for large-scale projects on your router table. Build large chests, guitar amps, cabinets and more! Just use the knobs to secure the MDF base of the jig into the miter slot of your router table—the sturdy steel sled then lets you guide the workpiece past the bit with complete control. The jig includes precision-machined aluminum indexing keys to give you air-tight joints with either 1/2'' or 3/4'' fingers. The vertical face of the sled features two sacrificial MDF boards that securely sandwich the workpiece and provide backup support for reduced tearout. Larger pieces can be supported easily by adding a 1/2'' piece of material to the left and right side of the jig platform. The jig is easy to setup and detailed instructions are included. Features: Easy-grip rear-mounted handle makes feeding your stock easy and ergonomic Sturdy steel frame handles heavy materials Stable MDF platform has low-friction melamine coating for added durability and easy cleanup Easy-grip knobs lock the base into your miter slot. Fits standard 3/8'' x 3/4'' miter gauge slot Use with up-cut spiral bits for the cleanest cuts without blowout (see #63008 and #57813, sold separately)