Tenergy 7.2V 2000mAh Replacement Battery for iRobot Braava 320/321 & Mint 4200/4205 2000mAh Higher capacity: 500mAh higher comparing to the original 1500mAh battery Fully compatible with iRobot models: Mint 4200, Mint 4205, Braava 320 and Braava 321 while offering longer run time. Battery life lasts for hundreds of cleaning cycles Easy to charge and connect Unit Dimensions: 29.5mm x 43.5mm x 54mm / 1.2" x 1.7" x 2.1"