Description:Suitable for 4040 series aluminum profiles.Main components are made of aluminium alloy, which is firm and durable.The L shape corner bracket used for setting up a right angle connection of the two aluminum profiles, insert the two ends of the L bracket into the groove of the profile, and tighten the set screw to fix the two profiles. Built-in connection with beautiful and simple features. Widely used for building industrial aluminum frame structures, 3D printers, CNC Routers, CNC laser cutters, Robotics Projects. Specification:Material: Aluminum AlloyHole Quantity: 2Hole Size: 20mm x 8mm / 0.79" x 0.31" (L*W) Total Size: 40mm x 35mm x 40mm / 1.57" x 1.38" x 1.57" (L*W*H) Package Content:10 x 4040 Aluminum Brackets.