Satechi Launches New USB-C Clamp Hub for M1 iMac - MacRumors
iMac USB C Hub Adapter 10Gbps, 5 in 1 USB C Hub for iMac 2021 USB-C Clamp Hub | eBay
USB C Hub for iMac 2021 24 inch – Purgotech
Hagibis iMac Hub with 1000Mbps RJ45, USB C 3.1, USB 3.0 Ports and SD/Micro SD Card Reader, USB-C Clamp Hub USB C Docking Station for 2021 iMac 24 inch (with RJ45)
Want USB ports on the front of your new iMac? Try these hubs - CNET
AliExpress
M1 iMac 2021 - USB-C HUB with Hard Drive Enclosure– The Apple Nest
USB-C Clamp Hub for 24-inch iMac
Sabrent 4-Port USB 3.1 Gen 1 Hub with HDMI Port for iMac HB-SIMC
USB C Hub for iMac 24 inch 2021, Minisopuru USB Hub Adapter Support M.