This aluminum profile accessory set includes 20pcs corner brackets, 40pcs 20 series M5 T-slot nuts and 40pcs M5*8 socket caps. Made of grade 8.8 carbon steel material, with nickel plating on the surface, fine rust resistance and performance. With wide scope of applications, suitable for use in European standard aluminum profile grooves. You can have a try. Specifications: Name: Aluminum Profile Connector Set Material: carbon steel Color: silver, black (optional) Package size: 100 * 100 * 20mm / 3.94 * 3.94 * 0.79in Package weight: 200g / 7.05ounce Packing List: 20 * Corner Bracket 40 * 20 Series M5 T-slot Nuts 40 * M5x8mm Hex Socket Cap