Generic LM317 Adjustable Voltage Regulator Step Down Power Supply Module With LED Meter Feature: Board core components: adjustable regulator ASIC LM317, 2A or less can be loaded, AC or DC voltage input, the output voltage is 1.25V-28V DC continuously adjustable, versatile DC board. Using double adjustment potentiometer: when using LM317T for adjustable power supply, often lead to output voltage increases and burned the load due to potentiometer poor contact. We designed this regulator board using double potentiometer to ensure good contact, effectively protect the load. Specification: Input: DC 0V ~ 30V / AC 0V ~ 22V Output: DC 1.25V ~ 28V Output current: 2A Max. The minimum differential between input and output: 3V, input must be higher than the output voltage above 3V to be regulated. Buck, not boost, when input 5V output 1.25V ~ 2V, not 6V. Circuit board size: 69 x 50 x 27mm ( L x W x H ) Note: Due to the digital voltage display module operating voltage is 3V, only when the voltage is higher than 3V to display properly Package included: 1 x LM317 adjustable voltage regulator step-down power supply module with LED meter