Model Number:W-160 Aluminum 2-Way Macro Focusing Rail Slider Plate CNC processing from solid aircraft-grade aluminum Color: black + red Precision focusing through a 110mm range Index Scale on both sides 48mm diameter metal thumbwheel with 1/4 inch-20 Screw. Arca/ compatible 55mm dovetail plate w 1/4 inch-20 threaded socket. Helping to achieve exacting camera-to-subject distance, the Macro Focusing Rail is a focusing stage offering fine- tuned control across a 115mm adjustment range The Rail is driven by a knob-controlled worm gear and index scales, in millimeters, are printed on both sides of the rail for consistency.. Cameras can be mounted on top of the rail via the integrated 1/4 inch screw, which uses a 48mm-diameter thumbwheel to secure cameras in place. 214mm overall length (including adjustment knob). Weight 293g (10.3oz). Package List: 2 * Rail Slider Plate Only 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. Material: Aluminum Alloy Adjusting Range: 115mm / 4.5in Load: max. 10kg / 22lb Item Weight: 292g / 10.3oz / pcs Package Size: 22 * 5.5 * 5cm / 8.7 * 2.2 * 2in. Package Weight: 330g / 11.6oz