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
2013 iMac teardowns reveal SSD slots, soldered-in CPU in the 21.5” model | Ars Technica