1Quick Release Plate with Bubble Level: The rail nodal slide features standard for Arca 38mm 2 way slot design for easy camera position adjustment. It is compatible for Arca ball head without the need to remove the camera, making it ideal for panoramic and macro photography. 2Multifunctional Design: Equipped with for Arca standard knob clamp, scales, and level, this plate is perfect for panorama and macro photography. The knob clamp can be stopped at a maximum opening of 50mm. 3Built in Bubble Level: It comes with easy to read scales on both sides for accurate adjustment. The built in bubble level ensures accurate horizontal orientation for photography. 41/4in Screw Hole: With multiple screw holes, the plate can be used to mount accessories such as microphone, flash, panel light, etc., making it convenient for outdoor film, live streaming, or any video recording. 5Easy Installation and Removal: The plate allows for quick release, rotation, and reinstallation of the camera. Made of aluminum alloy and accuracy CNC machining, it is sturdy and smooth. 1 x Camera Rail Nodal Slide 1 x Wrench