Electric Drill Battery Indicator LED Display for 18V /21V Lithium Batteries 18650 Capacity Visual T Optimized Battery Management: Easily monitor your battery's charge level with our LED display indicators, designed specifically for 18V and 21V lithium batteries. This tool is essential for efficient power management and prolonging battery life. Universal Compatibility: Our indicators are compatible with most 18650 lithium battery setups, making them a versatile addition to your toolkit. and Reliable: Crafted with quality materials, these indicators long-lasting performance and reliability in working conditions. Due to different batches, there may be differences in product appearance and printed text, which not affect use Color:Black Material:ABS Package Contents: 10 * Electric Drill Battery Indicator Display Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.