ITEM NAME:3/8-inch Steel T-Slot Nut Black Oxide Plated Grade 8.8 Tapped Through 8 pcs B1X4 3/8-inch Steel T-Slot Nut Black Oxide Plated Grade 8.8 Tapped Through 8 pcs B1X4 Black oxide finish, pressing thread forming and durable. Bottom of T-Slot Nut Is staked to prevent the stud from protrusion. It is used for T-slot aluminum extrusions to connect other parts. Undersized to fit machine table slot case hardened. Hardness: 23-32HRC Product Name: T Slot Nut Main Color: Black Material: 45 # Steel Grade: 8.8 Weight: 195g Dimension: 22 x 18 x 12mm/0.9 inch x 0.7 inch x 0.47 inch(L*W*H) Thread Diameter: 3/8 inch Slot Width: 11.5mm / 9/20 inch Coating: Black Oxide Plated Slot Depth: 6mm / 15/64 inch Package Content: 8 pcs x T Slot Nut 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..Black oxide finish, pressing thread forming and durable. Coating: Black Oxide Plated. Bottom of T-Slot Nut Is staked to prevent the stud from protrusion. Undersized to fit machine table slot case hardened.