PULUZ PU3520 CNC Aircraft Aluminum Adjustable Speed Fine Tuning Slide Rail for Canon Sony Nikon Camera •Lightweight Material: Precision CNC machined from solid aircraft aluminum for a lightweight yet sturdy design •Durable Anodized Finish: Features a high-level hard anodized finish that enhances surface durability and resistance to wear •Knob-Controlled Adjustment: The rail is driven by a knob-controlled worm gear,with index scales in millimeters printed on both sides for consistent measurements •Adjustable Sliding Speed: Allows for adjustable sliding speed; choose between slow precision or fast movement. The screw knob features a CNC cutting texture for better grip •Fine-Tuned Control: Helps achieve exact camera-to-subject distance with a focusing stage offering fine-tuned control across a 115mm adjustment range •Standard Dovetail Groove: Equipped with a standard dovetail groove,compatible with ARCA and RRS clamps. Compact and super lightweight for easy transport •Secure Camera Mounting: Cameras can be mounted using the integrated 1/4 inch screw,secured in place with a 48mm-diameter thumbwheel. Overall length is 214mm (including adjustment knob) Package included: •1 x Slide Rail •Other items not include