Helps you achieve true vertical hold for improved accuracy. Bright, fluorescent green bubble-level pivots out into the open position for immediate use and swings back over the top of the scope for storage. Accommodates both left and right hand scope games. Attaches to your telescope like a traditional scope ring, halves clamp together with two steel allen head screws. Easy-to-see offset level helps you make immediate corrections without taking your eyes off the target. Specification: Material: Aluminum Alloy Size(LW): Approx. 4.6 3.3cm/1.81 1.30inch Package Includes: 1 Piece 30mm Scope Bubble Level 1 Piece Screwdriver(3 Pack) Note: Please allow a slightly errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understanding and attention. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.