Electrical Parameters:Input: DC 3.2V to 35V (input voltage must be more than the output voltage can not be higher than boost 1.25v.)Output: 1.25V to 30V DC voltage is continuously adjustable, high efficiency and maximum output current of 3A.Features: All solid capacitors using SANYO, 36u thick circuit boards, high-Q inductors with high power output LED indicatorSize: 45 21 13mm / 1.69 0.83 0.51inch (including potentiometers)minimum with locating hole with LED indicator DC-DCInstructions:Access to power (3-35V), adjust the blue potentiometer knob (clockwise rotation generally boost, buck counterclockwise rotation) and with a multimeter to monitor the output voltage reaches the required voltage.Wiring:1. welding, welded directly to the power line input (output) port;2. solder pins, or pins can be inserted through the lead insertion use in tunnel plate; soldered directly to the PCB after another or add pins.Note: The input and output can not be reversed, reverse might burn chips;This is a step-down module, the input voltage is higher than the required output voltage;Output 2A or less long period of time without additional heat sink output current is greater than 2.5A (or output power greater than 10W) to work long hours please add heat sink.Package Included: 10pcs X LM2596S Module