Features: This 3S 40A lithium battery protections board is quality integrated components, not easily damaged and have stable performances. Equipped with thickened aluminum fins to accelerate heat dissipation, helping to effectively improve operational efficiency and provide excellent user experience. Adopting intelligent lithium battery management chip to ensures fast and safe charging. The design with multiple protections function, including overcharge, overdischarge, shortcircuit and temperature protections, multiple load and aging testing. Suitable for lithium batteries with nominal voltages of 3.7V and fully charge voltages of 4.2V (such as 18650, 26650, lithium batteries), it can use for power drills under 170W. Specifications: Material: Circuit Board Type: Balanced Board, Reinforced Board(optional) Balanced Board: approx. 60.3x40.9mm/2.37x1.61inch Reinforced Board: approx. 55.2x41.4mm/2.17x1.63inch Name: 3S 12.6V 40A Lithium Battery Protections Board Charging voltages: DC12.6~13.6V Continuous discharge current: up to 40A Continuous charging current: up to 20A Package Includes: 1 Piece 18650 Lithium Battery Protective Board note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.