27 "iMac selling with Retina 5K screen, final model of 2914.
Specifications:
Display: 27 "Retina 5K (excellent)
Processor: Intel Core i5 3.5 GHz (4 cores)
Extended RAM memory at 24 GB
Storage: 1.12 TB Fusion Drive
Graphs: AMD Radeon R9 M290X (2 GB)
USB 2.0 and 3.0 ports, Thubderboldt

NOTE: This model no longer receives official macOS updates (it stays in Big South macOS).
It continues to work perfectly, but is not recommended for very new or demanding software.