【Battery Specifications】 Battery Type: Li-ion; Voltage: 12V; Capacity: 4000mAh. The 4000mAh high capacity 8200 Li-Ion battery for Dremel provides longer run times and more power for your power tools 【No Memory Effect】 The B812-02 batteries are made from top A grade lithium, which are non-polluting, efficient, stable, have no memory effect and low self-discharge. Our B812-03 batteries can withstand up to 500 charge/discharge cycles without loss of capacity for maximum productivity and less downtime 【Perfect Compatibility for Dremel】 The professional replacement battery compatible with dremel B812-01, B812-02, B812-03. Fully fit for dremel tools models 8200, 8220, 8300 【Safety & Stability】Our 8300 batteries for Dremel comply with FCC, CE and RoHS certified. The 4000mAh Li-ion batteries built in protection microchip, preventing overcharging and over-discharging and prolonging battery life 【Warm Tip】 After using the 8220 battery for Dremel, you should wait for 15-30 minutes to cool down before charging, otherwise it will cause some damage to the B812-03 battery. If you have any other questions about the battery, please feel free to contact us Specifications: Voltage: 12V Capacity: 4000mAh Battery type: Li-ion Package included: 1 x Battery Why choose our Li-ion battery： 1, The 4000mAh high capacity battery provides your power tools with enough power to run for long periods of time and complete tasks efficiently; 2, Fully compatible with the original charger; 3, Made with lithium-ion cells, thus ensuring that no pollution is released into the environment; 4, The battery is designed with voltage stabilizing circuit, which can effectively eliminate the memory effect and low self-discharge rate. Tips for Li-ion battery use 1. Charge the battery after it has completely cooled down, and take proper breaks when using it in high-power tools. 2. It is recommended to use the battery at least once a month and clean the battery contacts with a cotton swab dipped in alcohol if necessary. Warm Notes: 1, Please make sure the battery you want to buy can match the brand, model and part number of your power tool. 2, Please store the battery in a dry, clean and cool place, and keep it away from heat sources and metal objects. 3, After using our batteries, please wait for them to cool down before recharge.