iMac (21.5-inch, Late 2012) - Technical Specifications
Identify the ports on your Mac - Apple Support
Sabrent Premium 4-Port Aluminum USB 3.0 Hub For 2012 iMac and later
Sabrent Premium 4-Port USB 3.0 Hub for iMac (2012 and later)
iMac (27-inch, Late 2012) - Technical Specifications
Identify your iMac model - Apple Support
iMac - Wikipedia
Sabrent 4-Port USB 3.0 Hub For iMac Slim Unibody (HB-IMCU) | HB-IMCU
iMac i5 3.2 27-inch (late 2013) ports/man… - Apple Community
increasing USB ports on iMac late 2012? | MacRumors Forums
Mac USB Ports Stopped Working? It's Likely Easy to Fix | OSXDaily
A Clever Way to Access the USB Ports on Your IMac (+ Video) : 5 Steps (with Pictures) - Instructables
Sabrent 4-Port USB 3.0 Hub For iMac Slim Unibody (HB-IMCU) | HB-IMCU
iMac - 9to5Mac
Aluminum Alloy Usb 3.0 Hub 3 Port Adapter Splitter With Sd/tf Card Reader For Imac 21.5 27 Pro Slim Unibody Computer - Docking Stations & Usb Hubs - AliExpress
Snowmous AccessIO for Easy Access to iMac's USB Port and Headphone Jack | Gadgetsin
Sabrent 4-Port USB 3.0 Hub For iMac Slim Uni-body (HB-IMCU) : Amazon.ca: Electronics