With standard 1/4" threads, scale plate and built-in bubble level, very convenient for use. Jaw can be opened from 37mm to 42mm, suitable for any Arca style plate such as RRS, Wimberley, Jobu Design, Arca Swiss, Kirk, Markins, etc. Features: Made of aluminum alloy, very durable and sturdy. Standard 1/4" threads, can be directly mounted on 1/4" thread of devices. Fast loading base with antiskid lock function. With scale plate and built-in bubble level, very convenient for use. Jaw can be opened from 37mm to 42mm, suitable for any Arca style quick release plate. Specifications: Material: Aluminum Alloy Color: Black Item size: 7.8 * 5 * 2.0cm / 3.1 * 2 * 0.8in Item Weight: 88g / 3.1oz Package Size: 8 * 5 * 3cm / 3.1 * 2 * 1.2in Package weight: 91g / 3.2oz Package List: 1 * Clamp for Quick Release Plate 1 * 1/4" Screw