Features: brand new and high quality High Quality hammer for head drop in for T slot nuts assortment kit These nut fasteners are made from high quality carbon steel, rust proof and corrosion resistant Easy to Install, can be directly into the aluminum slot hole in any of the assembly post, back spring ball can be fixed its position which make installation very simple and reliable Package includes 3 different sizes for T slot nuts packed in a durable transparent plastic box, 60 pieces M3, 60 pieces M4, 60 pieces M5, 180 pieces in total, meet your different needs The for T Nuts can be widely used for building industrial aluminum frame part, 3D printers, CNC Routers, CNC lasercutters, robotics projects, 3D carvers, machine guards, workstations, etc Specifications: Color: Sliver Drive System : Slotted Exterior Finish: Nickel Finish Type Silver Material: Carbon Steel Opposing Screw Size M4 , M3 , M5 Thread Size m3-0.5, m4-0.7, m5-0.8 Size: approx 13x7x2.2cm/5.12x2.75x0.86in Quantity: 180PCS( M3 M4 M5, 60PCS Each ) Package Includes: 60 Pcs x T-Nuts M3 60 Pcs x T-Nuts M4 60 Pcs x T-Nuts M5 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 0-2cm.