Circuit BoardsFeture2S 40A 3.7V Same PortCharging protection voltage: 4.28VDischarge protection voltage: 2.9VEqualization function: YesEquilibrium current: 90mAMaximum sustainable current: 40ACurrent limit protection: 225AShort circuit protection: YesSize: 63 * 47 * 7MM2S 40A 3.2V Same PortCharging protection voltage: 3.75VDischarge protection voltage: 2.1VEqualization function: YesEquilibrium current: 90mAMaximum sustainable current: 40ACurrent limit protection: 150AShort circuit protection: YesSize: 63 * 47 * 7MMHeat Sink Versionif no heat sink you choose you will only get PCB verison