Feature: 1. Multi-specification Optional: This adapter is designed for recharging lithium batteries, with three optional voltages of 16.8V, 18V, and 21V. It can be widely applied to a variety of lithium tools with different voltage requirements, enhancing practicality and meeting the needs of various devices. 2. Efficient Charging: Utilizes advanced charging technology to quickly recharge lithium batteries, shorten charging time, improve working efficiency, and effectively extend battery lifespan. 3. Multiple Protections: Built-in safety mechanisms include overcharge, overheating, and short-circuit protection. These features enhance charging safety and help reduce battery damage or potential safety risks caused by improper charging. 4. Fine Craftsmanship: Constructed with high-quality materials and a rigorous manufacturing process to ensure durability, reliability, and stable performance in various environments for long-lasting service. 5. Portable Design: Compact and lightweight, this adapter is easy to carry and suitable for multiple applications. Equipped with an LED indicator to provide real-time charging status, making the process clear and intuitive. Specifications: Name: Battery Power Adapter Material: Plastic + metal Output voltage: 16.8V, 18V, 21V (selectable) Input voltage: 100–240V AC Current: 1A Item size: 87 x 50 x 68mm / 3.43 x 1.97 x 2.68in Item weight: 69g / 2.43oz Package size: 100 x 80 x 60mm / 3.94 x 3.15 x 2.36in Package weight: 73g / 2.57oz Packing List: 1 x Battery Power Adapter