ITEM NAME:Drop In Post Assembly M4 T-nut for 20 x 20 Aluminum Extrusion 100 pcs W6A5 Drop In Post Assembly M4 T-nut for 20 x 20 Aluminum Extrusion 100 pcs W6A5 Post-Assembly T Nut Drop in T nut easier to install Suitable for 20x20mm T Slot aluminum extrusions Neck Width: 6mm; Thread Diameter: 4mm (M4) Color: Silver Material: nickel plated carbon steel Specifications: M4-20 Packakge list: 100 * Post-Assembly T Nuts Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm..Drop in T nut easier to install. Material: nickel plated carbon steel. Suitable for 20x20mm T Slot aluminum extrusions. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing.