Battery charger model SH-CDQ005-UL  is the replacement charger for the Ecotric Hammer and the 48v FAT Folding electric bicycle:

This is an original lithium battery charger for Hammer, Fat 20 48V. The charger case is made of PS/ABS material, high-temperature resistance, fire retardant, safe and durable, and also helps heat dissipation. FEATURES Compatibility：

• Hammer, Fat 20 48V. Input Characteristics : Nominal Voltage: 100-
• Ecotric 48v FAT Portable Electric bicycle
  
• Model SH-CDQ005-UL charger is compatible with 750w and 1,000w Hammer
  
• Compatible with UL rated and not UL rated bikes.