The upgraded version has a little more capacity so you'll get more flashes out @ full power (300 according to Profoto). Older B1 500 units need to have the actual Firmware or bigger than "E3" installed to run with these batteries.
- Provides up to 325 full-power flashes.
- Charges in just over two hours with the standard Battery Charger 2.8A.
- Charges in one just over one hour with the fast Battery Charger 4.5A.
- Charges in three hours with the Car Charger 1.8A plugged into a 12V connector.