<p>Features: Quickly and easily level your optics in the outdoor, at ranges, or at home.</p> <p>Convenient storage and transport, Great for long ranges shootings, perfect level.</p> <p>Suitable for 20mm\/11mm leads rail, can installed quickly and easily for rail.</p> <p>Use this bubble level to make surely your rifles level shootings the targets.</p> <p>Mounts quickly and easily to the rifles scope tube.</p> <p>Specifications: Materials: Aluminum alloys</p> <p>Clamping Size: 20mm(0.79inch)\/11mm(0.43inch)</p> <p>Package Includes: 1pc Scope Bubble Level</p> <p>note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color.</p>