noeifevo 29 4v 10a lithium batterieladegerat fur 25 9v 7s batterie automatische abschaltung aluminiumgehause mit lufterSince some batteries with an M25 charging port have built in charging protocols, our charger does not support these batteries. Please check with the battery manufacturer before purchasing whether the battery has an integrated charging protocol. For M25 (2+1+5) and M25 (2+4), the standard polarity is 1+ for positive and 2 for negative. If you require a different polarity, please let us know. Contact: You can reach us online or by email at