A Great Gift Idea For Dad, Mom, Husband, Friends And Family, Suitable For Everyone Who Needs It, Whether You Are A Professional Or An Average Person. Any Non-human Damage Or Any Reason You Are Not Completely Satisfied With Our Product, We Will Immediately Provide You Replace Your Item. Type: 4.0AH Battery Rated Voltage: 21V Power Input: 400W Charger Input: 110V, 50Hz-60Hz Parameters Display 4 led electric quantity display Number of Batteries: 1 Battery Weight : 20 OZ Cells Per Batter: 10 Compatible : For ALLOYMAN, Abeden, NCOEN, Aoben, Bomves, seesill, NCOEN, Inquire to learn more about compatible brands. Type: Battery power adapter Material: ABS Plug type: US Input voltage: 100-240V 50HZ/60HZ Interface: about 5.5*2.5mm/0.2*0.1in Output current: 1A Weight: 2 OZ How to install battery Step 1: Hold the machine firmly with one hand. Push down the battery unlock button located on the rear side of the battery with the other hand.Step 2: Keep pushing the unlock button down and slide the battery backward out of the machine.Step 3: You made it. Note： 1. Do not try to open the battery. 2. Protect the battery against continuous intense sunlight, fire, water, and moisture. 3. Do not damage the battery with sharp objects. 4. Do not discard this product at will. 5. Overcharging the device will reduce the life of the battery, unplug it from the charger in time to avoid overcharging. 6. If the battery does not last 10 minutes, it may be caused by overheating. Please wait for 5 minutes for the battery to cool down. Please read the following notes on battery maintenance carefullyAfter receiving the product, please fully charge the battery before using it.In order to protect the battery, please do not charge the battery for a long time. The best time to charge is not more than 6 hours.Please do not charge the battery all night, it will seriously damage the battery life.Always remove battery pack from your tool when you are assembling parts,making adjustments,cleaning,or when not being used for an extended time.Do not leave the battery dormant for long periods of time. We recommend using the battery at least once every two to three weeks. 21V Lithium Battery With Electric Quantity Display 4.0AH 21v lithium battery 4.0AH 21v lithium battery2.0AH 21v Battery Single Port Charger Base 21v Battery Dual Port Charger Base Buying Options Buying Options Add to Cart Buying Options Buying Options Customer Reviews 4.6 out of 5 stars 201 4.5 out of 5 stars 594 4.5 out of 5 stars 594 4.6 out of 5 stars 149 4.6 out of 5 stars 74 Price $27.99$27.99 $25.49$25.49 $19.99$19.99 $14.27$14.27 $23.79$23.79 Battery 4.0Ah battery 4.0Ah battery 2.0Ah battery compatible compatible Battery Power Ddapter ✓ ✓ ✓ ✓ ✓ Electric Quantity Display ✓ no data no data no data no data Port: no data no data no data Single Dual