Features: Quickly and easily level your optics in the outdoor, at ranges, or at home. Convenient storage and transport, great for long-range shooting, provides a perfect level. Suitable for 20mm/11mm rail systems, can be installed quickly and easily. Use this bubble level to ensure your rifle is level when shooting at targets. Mounts quickly and easily to the rifle scope tube. Specifications: Materials: Aluminum alloy Clamping Size: 20mm (0.79 inch) / 11mm (0.43 inch) Package Includes: 1 x Scope Bubble Level Note: Please allow 1-2 cm errors due to manual measurement; ensure you are comfortable with this before ordering. Due to differences between monitor displays, the picture may not reflect the actual color of the item. Additional Notes: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error; ensure you are comfortable before ordering. 2. Due to lighting in photographs and differences in monitor settings, images may not reflect the exact color of the item. Please confirm you are comfortable with this before placing your order. About Shipping: 1. Please ensure your delivery address is correct, including name, street, house number, doorbell/email, etc., to avoid delivery issues. 2. All items will be shipped within 3 business days after payment is received. Delivery typically takes 812 days, depending on location. 3. If you have any questions during the shopping process, please . We will respond within 24 hours. We hope you have a pleasant shopping experience!