Features: 1.Portable counter precision buttons, accurate counting, and long button lifespan. 2.Equipped with self-locking function to avoid data loss caused by misoperation. 3.Oled display screen, displaying battery level, time, date, and count. 4.Type-c charging, long-lasting battery life, built-in 75mah rechargeable battery. 5.The ring has three adjustable gears, which is convenient and practical. Parameters: Product name:ring counter Product model: s7 Input voltage: 3.7 (v) Battery capacity: 75mah Counting range: 0~9999 Product specifications: adjustable (1st gear 18mm, 1st gear 20mm, 1st gear 22mm) Color: Black Green Material: ABS Package Contents: 1 x Counter 1 x charging cable 2 x Adjusting ring 1 x English instruction manual 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.