b' Features: Built-in two bubble level, which ensure the photography stable and leveled, easily find the correct shooting direction no matter horizontal or vertical shooting. 38mm Arca-Swiss standard U-shaped grooves of the clamp, which can protect your camera from accident drops. With three 3/8 thread screw hole and two standard 1/4 thread hole for tripod monopod ball for head. for any arca style plate, camera bars and multi-purpose rails. such as RRS, Arca-Swiss, KIRK, Wimberley, Markins, Sunwayfoto, Kangrinpoche, Benro etc. Specifications: Material: Aluminum Alloy Size: Approx. 70x38x15 mm/2.76x1.5x0.59 inch Card Slot: 38mm Color: Black Qty: 1 Pc Note: Please allow 1-2cm errors due to manual measurement,pls make sure that you do not mind before you mind. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package Includes: 1 Piece 70mm Quick Release Clamp