[Instructions for use] This accessory enhances stability when using a telephoto lens and a tripod. It mounts on the lens barrel and secures the lens to the tripod through the tripod socket under the tripod mount. Additionally, the camera can be rotated around the lens by simply loosening the rotation lock knob of the tripod mount, allowing for easy switching between portrait and landscape compositions without tilting the gimbal. Attaching and Removing the Tripod Ring involves turning the locking knob counterclockwise to align it with the dot. Then, pull the knob outward to open the loop. With the loop open, place the lens in the tripod ring. Unscrew the locking knob of the tripod ring to rotate the camera and lens mounted on the tripod for horizontal and vertical positioning. After adjusting the camera to the desired position, tighten the locking knob. A tripod ring can be used on a circular tripod head. Made of aluminum alloy, with a one-piece body and CNC precision machining, it is durable and wear-resistant. Unique design ensures better protection for your camera. The tripod ring is constructed from high-strength metal, providing safety when used with the lens. Precision all-metal material processing and surface hardening treatment enhance its durability and wear resistance. The lens ring features a 1/4 screw hole at the bottom; the inner flocked lens holder with locking knob tightly secures the lens without any gaps, making it sturdy and durable. [Basic function] It firmly fixes the lens on a tripod and allows for convenient rotation to meet various needs. Ring inner diameter: 81mm Ring width: 18mm Applicable lenses: (compatible with the following lenses) suitable for a specific 70-300mm lens and a specific Zoom-Nikkor lens. Colour: black Material: aluminum alloy Package Contents: 1 * Tripod Mount Ring Only the above package content, other products are not included. Note: Light and different displays may cause the item's color to differ slightly from the real thing. The measurement allowed error is +/- 1-3cm.