noeifevo 42v 4a lithium charger for 10s 37v li ion lipo batteries with lcd display cooling fan automatic shutoffDue to some batteries with M25 charging ports that have integrated charging protocols, our charger cannot support batteries with built in charging protocols. Please confirm with the battery supplier before purchase 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: You can