This backpack style battery carrier is compatible with our entire range of portable EGO Power + batteries and connects to the harness/hip belt (AFH1500) which is also compatible with BAX1500 backpack battery. Now you can work with any battery & hand-held tool in the EGO range with just a single harness. Ideal for customers that already have BAX1501 (supplied with harness AFH1500) and would like to use portable batteries also.