(Note: 21.9V is Pool Cleaner's battery voltage. NOT charger's voltage. Please Check For Compatibility With Your Unit. Thanks.) World Wide Input Voltage 100-240VAC 50/60Hz OVP, OCP, SCP Protection (OVP: Over Voltage output Protection. OCP: Over Current output Protection. SCP: Short Circuit output Protection) UpBright New Global 2-Prong AC / DC Adapter Compatible with Hydrus Seauto Shark SE Shark-SE SharkSE 21.9V 10400mAh 227.76Wh DC21.9V 10.4Ah 21.9 Volt 10400 mAh 21.9 Volts 10.4 Ah 21.9VDC Lithium ion Li-ion Liion Rechargeable Battery Pack Model SAT-4P6S SAT4P6S MX120Z-25204000 MX120Z25204000 Cordless Automatic Robotic Swimming Pool Spa Vacuum Cleaner Class 2 Switching Power Supply Cord Cable PS Charger Mains PSU (w/ 2-pin Connector) Note: Rechargeable batteries don't last forever, the average battery last 1 to 3 years. If the battery is old/bad, it will not accept a charge. But not charger's problem Compatible with listing item: Shark Cordless Robotic Pool Vacuum Cleaner Waterline Cleaning, Wall-Climbing, Intelligent Route Planning (Multi) Tested Units. In Great Working Condition. UpBright 30 days Refund. 24 Months Exchange UpBright New Global 2-Prong AC / DC Adapter Compatible with Hydrus Seauto Shark SE Shark-SE SharkSE 21.9V 10400mAh 227.76Wh DC21.9V 10.4Ah 21.9 Volt 10400 mAh 21.9 Volts 10.4 Ah 21.9VDC Lithium ion Li-ion Liion Rechargeable Battery Pack Model SAT-4P6S SAT4P6S MX120Z-25204000 MX120Z25204000 Cordless Automatic Robotic Swimming Pool Spa Vacuum Cleaner Class 2 Switching Power Supply Cord Cable PS Charger Mains PSU (w/ 2-pin Connector) CECCCROHS 100-240