noeifevo 60v 4a lead acid battery charger oled display aluminum case intelligent fast charger xt60 xt90 iec c13 dc5 5 21 2 5Since some batteries with an M25 charging connector have integrated charging protocols, our charger does not support these batteries. Please check with the battery manufacturer before purchasing to confirm 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 information: You can reach us