Description: 1: input: 4.5 V DC - 7 V (input voltage must be wining the to the output voltage high 1 V above.) 2: the output: 3.3 V, 800 mA (the load current can 't wining 800 mA) 3: PCB size: 8.6 * 12.3 mm Attention: 1: the Boost modules or buck module indicate the operating voltage, both Please donot exceed operating voltage, or it will be on easily! 2: the Boost module output voltage can only be greater than or equal to the input voltage, always be less than the input voltage. 3: Buck module input voltage must be who the output voltage of 1.5 V or 2 V, otherwise it can not output the enough power! 4: Automatic Adjustable Boost or Buck the module from the start voltage and limit the working voltage, both Please donot exceed them, or it will be on easily! 5: always reverse polarity, or it will be short circuit, or will be born easily!