The ddHiFi TC28i Pro adapter allows smart devices with a Lightning connector to remain OTG enabled while charging. So one Type-C socket is perfect for connecting data storage devices and DACs (digital-to-analogue converters), while the other Type-C socket is for charging only (10W). The small but smart adapter is built in a durable CNC-milled aluminium alloy housing. The sound quality is improved when listening to music while charging! The product is not Fast Charge compatible!