I bought them to use with my new 2021 M1 iMac which has 2 USB3 (USB-C) ports and 2 Thunderbolt/USB4 ports has. 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 flash drives etc. These adapters cost 1/4 the price of an original Apple adapter, although I bought one from Apple to make sure there were no problems.