I bought them to use with my new 2021 iMac M1 which has 2 USB3 (USB-C) ports and 2 Thunderbolt/USB4 -Has connectors. These adapters allow me to connect all four ports to legacy USB 2.0 and 3.0 devices. They are very well made and connect easily and securely to legacy USB devices. I dangle one from the front (see photo) so I can easily connect Garmin GPS units, iPhones, flash drives, etc. These adapters are 1/4 the price of a genuine Apple adapter, although I bought one from Apple to make sure there were no problems becomes.