INTELLIGENT DESIGN: UPS for 4B / 3B+ / 3B. Built-in path management, support side-loading, load high current line compensation function. There are two USB A port output, and also adds type C output. It provides uninterruptible for the to make your still work while moving, and its design is so smart that you can troubled of a mass wire.You can check the link in the Product guides and documents at the bottom of the page. MULTIPLE PROTECTION: Support output overcurrent, overvoltage, short circuit protection; input overvoltage, overcharge, overdischarge, overcurrent discharge protection and machine overheat protection. Safe and reliable USE AND NOTE: This product belongs to the supply device. Please keep it out of the reach of children. Please strictly refer to the instructions for the UPS product, install the battery first, then connect the UPS to the . Please do not reverse the battery. If the battery polarity is reversed, it will directly burn the management chip of the device. Do not add any Components by yourself FAST CHARGING SUPPORT: Support FCP, , SFCP fast charge protocol maximum, support 18W protocol, 20W input FUNCTION UPGRADES: Support 4.2V 4.35V 4.4V 4.5V lithium battery, supply side current, voltage, monitoring, Note: Different types of batteries cannot be mixed Material:Plastic + Metal colour:black Package Contents: 1 set x Expansion Board 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.