It came out of the box fully assembled, with backer board installed, and we completed a joint in only seven minutes, with no need to adjust for a perfect fit. The edge stops work great at positioning the workpiece, and it required a 5/32" Allen wrench (included) to remove the 1" spacers. We love that it has variable-spacing available for the guide fingers, so you can adjust the size to suit your project. The optional handles for router-table use seem unnecessary, since you can hold the jig by the body to do the work.