iMac: Get a refurbished 2011 21.5" Core i5 iMac! Operating system: Mac OS High Sierra operating system (released in 2017). Display: With a 21.5" 1920 x 1080 native LED-backlit 16:9 widescreen display. Processor: Quad Core 2.5 GHz Intel "Core i5" I5-2400S (Sandy Bridge) processor. Connectivity: Four USB 2.0 ports, a Firewire "800" port, built-in AirPort Extreme, a Thunderbolt port, Gigabit Ethernet and an SDXC card slot. RAM & storage: Choose 4GB, 8GB or 16GB RAM, and 1TB HDD, 256GB SSD or 512GB SSD internal storage. Features: Plus a FaceTime HD webcam and stereo speakers. | Apple 2011 21.5" Core i5 iMac - 4GB | Wowcher