This is for a set of hold down clamp for use with T-slot track.These clamps are useful in many woodworking & metalworking applications for work holding, positioning, and fixturing.Puts clamping pressure anywhere along the flush-mounted T-slot T-track.Slides into T-track & quickly secures with the turn of the hand knob nut.Both T-screw and threaded rod are of 8mm threaded. for building jigs and fixtures for your radial arm saw, workbench, drill press, and various other machines.Colour: silverMaterial: aluminum alloySize: 23x30mmPackage Contents:4 * M8 sliders4 * T screws4 * M8 nutsOnly the above package content, other products are not included.Note: Light 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.