The 6 hole - wide 2x4 inside corner bracket is an external fastening method that creates a 90 degree connection. One side of the bracket has two adjacent holes and the second side has four holes comprised of two rows and two columns. This fastener requires no machining services and can provide infinite positioning along the profile T-slot, allowing a large degree of adjustability. It engages the 2-degree drop-lock feature when the assembly bolts are tightened to the required torque and can also be repositioned and reused. The suggested mounting hardware can be found on the "Suggested Hardware" tab.