8.4V Tenergy 5000mAh Flat NiMH Battery Pack with Tamiya Connector Easy operation, battery can be charged anytime without the need to fully discharge. Advanced NiMH battery technology, no battery memory effect. Compatible with Most AirSoft electric guns:MP5SD5, G3SD1, M16VN, FAMASF1, M1AI,KNIGHTS SR16, MP5A4, G3A3, AK47, ASSV, and PSG1 Dimensions: Height 22.5mm; Width 46mm; Length 158mm Maximum Discharge Rate: 40A