Review on 🔌 Cable Matters 4K Mini DisplayPort to Mini DisplayPort Cable in White 3 Feet - Thunderbolt Incompatible, Excludes iMac & Target Display Mode Support by Mark Hart

If you are trying to convert your old iMac's 27 inch screen (I have a mid 2010 model) to your old MacBook to use (my macbook pro is 2015) this is the cable you need. It took me a while (and a few failed attempts with other cables) to find this one and it works great. You can toggle (using F2 on your iMac) to switch between an external (and extended/dual) monitor for your MacBook and your iMac's home screen (for use as a standalone iMac, or as a multitasking app on your iMac while you're doing something do anything else on your MacBook). ). VERY practical and helpful. And this cable is great for the job. [Warning: If you have a more modern iMac and/or MacBook you probably only need a Thunderbolt cable, but for older versions this is the ONLY cable. That will work)