Features: This 20A lithiums battery protections board offer high current capacity up to 30.0a, for electric tool battery circuits, with builts in safeguards against overcharge, over discharge, and short circuits to ensures long lasting performances and safety. Featuring 5series design for 18V/21V batteries, the PCB with electronic components provide stable voltages output, thermal protections to cut power during overheating, and lightweight construction for easy installation without adding bulk. for enthusiasts and professional workers using electric tool, it allows seamless upgrades to existing battery systems, catering to users who demand power for high intensity tasks. Perfect for demanding scenarios like operating brushless wrenches, angled grinders, and electric hammers, this electric tool battery circuit ensures consistent output and extended battery life in workshops or job sites. With broad compatibility for various tool and intelligent protections features, this 20A lithiums battery protections board secure, efficient operations, enhancing tool reliability in industrial and home environments. Specifications: Materials: PCB+electronic components Size: 4x 4.6cm Quantity:1PC,3Pcs,5Pcs(optional) Package Includes: 1/3/5Pcs Battery protections Board note: Please allow 0-1cm error due to manual measurement. make sure you not mind before bid. Due to the differences between different monitors, the Pictures may not reflect the actual of the item.