The 6 hole - rectangular flat plate is an external fastening method that requires no machining services. It is a durable connection that can be easily repositioned and reused. The flat plate can provide infinite positioning along the profile T-slot, enabling a large degree of adjustability. When the bolts are tightened to the required torque the 2-degree drop-lock feature is engaged, helping to ensure the strength of the connection. The suggested mounting hardware can be found on the "Suggested Hardware" tab. Tip: Use a double slide-in economy T-nut and pre-load your hardware prior to connecting profiles to save time and money.