SSD Upgrades for Apple iMac 27-Inch Late 2013 - 2019
Upgrading an older iMac's PCIe SSD: Third-party solutions that save you beaucoup bucks | Macworld
OWC OWCS3DAPT4MA20K 2TB Aura Pro X2 SSD Upgrade Solution for iMac (2013 - Later) - High Performance NVMe Flash
M Key NVMe PCIe M.2 SSD Adapter Card Expansion Card for 2013 2014 2015 2017 Macbook Air 27' imac 2013 2014 2015 2017 - AliExpress
Timetec 256GB MAC SSD NVMe PCIe Gen3x4 3D NAND TLC Internal SSD Compatible with Apple MacBook Air (2013-2015, 2017), MacBook Pro (2013-2015), iMac ( 2013-2019), Mac Pro (2013), Mac Mini (2014) - Walmart.com
iMac 2013 (and later) with NVME SSD? | MacRumors Forums
How to use an NVMe drive to upgrade your Mac's SSD | AppleInsider