noeifevo 37 8v 2a 3a 3 5a 4a lithium charger for 9s 33 3v li ion lipo batteries cooling fan automatic shutdown blueDue to some batteries with M25 charging connectors that feature integrated charging protocols, our charger cannot support batteries with built in charging protocols. Please confirm with the battery supplier before purchasing whether the battery has an integrated charging protocol. For M25 (2+1+5) and M25 (2+4), the standard polarization is 1+ for positive and 2 for negative. If you require a different polarization, please let us know. Contact options: