Apple iMac with Retina 4K Display (21.5-inch, 8GB RAM, 256GB SSD Stora – 6ave Electronics
Install memory in an iMac - Apple Support
Apple iMac (27-inch, 2017) review: Apple doesn't mess with success - CNET
Install memory in an iMac - Apple Support
iMac 21.5-inch 4K (2017) Review | Trusted Reviews
Apple A Grade Desktop Computer iMac 21.5-inch (Retina 4K) 3.4GHZ Quad Core i5 (Mid 2017) MNE02LL/A 8 GB 1 TB HDD 4096 x 2304 Display Mac OS Includes Keyboard and Mouse - Walmart.com
iMac (21.5-inch, 2017) - Technical Specifications
iMac 21.5-inch 4K (2017) Review | Trusted Reviews
A-Tech 16GB (2x8GB) RAM for Apple iMac 2017 (27 inch Retina 5K & 21.5 inch Retina 4K) | DDR4 2400MHz SODIMM PC4-19200 1.2V 260-Pin SO-DIMM Memory Upgrade Kit at Amazon.com
Apple 21.5" iMac with Retina 4K Display (Mid 2017) MNDY2LL/A B&H