Product description<br>Input voltage: 5V<br>Charge cut-off voltage: 4.2 V ± 1%<br>Maximum charging current: 1A<br>Over-discharge protection voltage: 2.5V<br>Overcurrent protection current: 3A<br>Size: 26 x 17 mm<br>Battery holder<br>Type: 3.7V<br>Material: durable plastic<br>Size: 75 x 20 x 13 mm<br>Product List:<br>3 x boost converters<br>3 x charging module<br>5 x battery holder<br>1. 【Boost Converter】: With this mini boost converter, you can easily create a power supply unit such as 9 V, 12 V, 15 V, 18 V, 24 V etc. with adjustable output yourself. Boost Converter: Used only to increase the voltage and not to decrease the voltage.<br>2. 【Steps for Boost Converter】: Connect the power supply, turn the twist knob on the blue potentiometer 15 to 20 rounds counterclockwise and monitor the voltage with a multimeter to get the required voltage.<br>3. 【Battery holder】: The battery holder is intended for a 3.7 V 18650 lithium-ion battery.<br>4. 【Wide range of applications】: DIY mobile power supply, power supply monitoring, camera power supply, vehicle power supply, communication equipment power supply, etc.<br>5. 【Compatible】 ： Each level shifter can convert 4 pins on the high side to 4 pins on the low side, with two inputs and two outputs for each side. Power input with anti-reverse connection protection, built-in 3.3VLDO and can supply an external current of no more than 150 mA. Compatible with breadboard, can be used in breadboard directly