Feature: 32 Strength Levels Free to adjust strength levels to give your muscle a deep massage ideal for muscle recovery after exercise. Long Working Time With rechargeable large-capacity lithium battery you can use it for a long time. Super Silent Designed with low noise motor it produces noise under 45db Feel free to use it without worry about disturbing others. Auto Power Off This massager will automatically power off after 15 min to injuries due to long-time use at the same part of the body. Comfortable Grip The handle of the massage is ergonomic and sweat-proof which is very soft and comfortable. Detachable Massage Head Our muscle massager offers 4 types of massage heads to meet the needs of different parts needed massaging. The massage head can be removed for easy installation and cleaning. Specification: Color: Black Grey Red Green (Optional) Strength levels: 6 32 (Optional) Interface: Type-C Material: ABS Output voltage: 7.4V Packing list: 1 * Muscle Massager 4 * Massage Heads 1 * Charging cable 1 * User manual