Product parameters: input voltage is 4.0 V - 40 V, output voltage is 1.25 V - 37 V, output current is 2 A (normal and stable) and maximum 3 A, conversion efficiency 92% (highest), output ripple under 30 mV, switching frequency 150 kHz, operation temperature is -45 to 85 degrees Celsius. Easy to use: the voltmeter can be turned off, and the switch can be turned off by holding the switch longer than 1 second and less than 4 seconds. Once the voltmeter is switched off, simply press the switch to turn on the voltmeter. EASY TO USE:With terminal block, no soldering iron is convenient to use and maintain the wire connection point (the input voltage must be higher than the voltage output 1V or more). Output current: the maximum output current can be up to 3A, the recommended working current is . 2A, more than 2A plus heat sink Beautiful design: with an internal oscillation frequency of 150 kHz, low power consumption and high efficiency; if the output voltage cannot be adjusted and always matches the input voltage, please turn the potentiometer more than 10 revolutions counterclockwise, then adjust the voltage with the module normally. This is because the standard output voltage when leaving the factory from the factory . 20 V. Material:Plastic + Metal colour:Blue Package Contents: 6 x LM2596s Converter DC to DC Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.