These allow iOS devices to work with class compliant USB devices, such as audio and midi interfaces, and access media (from iOS 13 onwards) without the camera connection kit. These are Apple MFI certified.
15cm and 1.2m variants available, along with a 15cm version with USB-B micro input for charging
Manufacturer has stated this is incompatible with:
Dji Mavic Pro, Dji Spark, Shure MV51, COZOY Astrapi, Fiio Q1 Mark II, Fiio Q5 and other MFi DAC products