Glue joining router bits make stronger glue joints possible by creating more gluing surface.  Use our 45 degree lock miter router bit for those 90 degree corners where a solid glue joint is required and you don't want nail or screw holes complicating things.  This type of router bit also comes in a 22.5 degree router bit profile.  The drawer lock lock router bit creates the same effect but is used mainly for securing drawer fronts to the drawer body while hiding the joint.  For gluing edges together, choose either the glue joint router bit or the tongue & groove router bit.