Material: AluminumModel: NNR-140Screw Thread: UNC 1/4"-20Size: . 17 x 3.7 x 1.4cm/ 6.69 x 1.46 x 0.55"Jaw can be opened from 40mm to 45mmIt is widely used with fish-eye-lenses and wide-angle lensesSafety stop relief grooves for protecting your camera from accidental Machined from light weight aircraft-grade aluminum, sealing it against corrosion and abrasion, has two safety stop screw on back of plateStandard dual dovetail design, with high contrast built-in bubble level to improve alignmentScale on both sides of the rail to adjust the nodal point conveniently and accuratelyClamp with screw-knob help you locking equipment quicklyAccurately find nodal point for panoramic photographyDesigned with 8pcs UNC1/4 screw thread for extended functionPackage Included: 1 x 140mm Nodal Slide Rail Quick Release PlateNote: 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."