Charger for WireFree battery pack/RTS Li-Ion motors 9021027 Roll Up 24 WF RTS Li-Ion - 1240279 Roll Up Basic 28 WF RTS Li-Ion - 1241444 Sonesse 28 WF RTS Li-Ion - 1003296 Sonesse Ultra 30 WF RTS Li-ion - 1003310 Also compatible with battery pack 9021217.
eBay