This gear fits the Rokinon 14mm f/2.8 ED AS IF UMC lens. Double check that the aperture ring on your lens is the same as the one pictured (small in diameter than focus ring). 

It’s specially designed to fit this lens and is compatible with any standard 0.8 Module follow focus unit. Focus gears are generally slim for a clean, low profile gear that slides smoothly onto your lens and into your current lens case. Custom spec gears can be made on request. The gears do not have to be removed after each use although you can if you like. Each gear comes with a lifetime of support.

14