Tenergy Li-ion 22.2V 2000mAh Replacement Battery for Dyson DC31, DC34, DC35 (Except TypeB), DC44 (Type i, NOT DC44 MK2) 917083-09, 91708309 Handheld Vacuum Cleaners Longer Runtime - Capacity of 2000mAh provides 30% longer run time than OEM 1500mAh battery. Full Compatibility - Its fully compatible with Dyson DC31, DC34, and DC35, DC44 (Type i, NOT DC44 MK2) handheld vacuum cleaner. Just plug in & use, no other tools needed. Compatible models from: DC31, DC31 Animal DC34, DC35, DC35 Exclusive, DC35 Origin Exclusive, DC35 Origin Exclusive (Except Type B) DC44 (Type i, NOT DC44 MK2) 917083-01, 17083-2811, 18172-01-04, 17083-4211, 18172-0201, 917083-03 Smart and Safe - The battery has built-in protection against potential damage caused by overcharging, overheating and short-circuit protection. 22.2V 2000mAh Li-Ion