Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter
Apple MMEL2AM/A Thunderbolt 3 USB-C to Thunderbolt 2 Adapter for sale online | eBay
Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter - Apple
Amazon.com: Plugable Mini DisplayPort (Thunderbolt 2) to HDMI Adapter - Driverless (Supports Mac, Windows, Linux, and 4K Displays up to 3840x2160@30Hz, Passive) : Electronics