Features:The rotating direction can be changed so the inlet and outlet are interchangeable.The input voltage is from 3V to 12V DC, terminal with red dot is the positive electrode.5V 2A power supplysuch as battery holder or computer USB is recommended for long time work.The pump uses RS-360SH motor and the maximum head can be up to 1.5 meter.Widely used for aquarium, fish , bonsai, rockery, water cooling system for laptop or many experiments.Specifications:Rated Voltage: 3V12VDCMotor Diameter: 27mm / 1.06inPump Head Diameter: 44mm / 1.73inLength: 60mm / 2.36inInlet/Outlet Diameter: 4mm / 0.15in. Head: 1.5M / 4.9ftNote:1, Please do not connect it to 7.5V or higher voltage for a long time.2, Single dry cell battery, mobile phone charger and other chargers can NOT be used as a power supply.3, All power supply with a actual current less than 1.5A or actual voltage more than 12V can NOT be used otherwise the pump will not work or might burn out.4, The pump is not a submersible pump, it can not be put in water.5, No-load test time should not be too long.6, Impurities in water should not be suck into the pump, so please make sure water is clean.7, If pump is stuck, open the front cover and clean.Package Includes:1 x Mini Pump