Allows grooves and tenons to be cut using a router can be used to crosscut boards with a router or circular saw frame is adjustable to allow narrower or wider grooves to be routed the max adjustment is 70mm depending on the diameter of the router base the edge of the frame can be used as a guide to trim a panel square using a router two sliding stops to set groove length squaring butt has the facility to accept a spelch block to allow a full length groove fixing screws are included for this purp