Compatibility: VILTROX EF-M2 II is an upgraded version of EF-M2, designed for Canon EF series lenses to be used on M4/3 mount cameras, such as GH4 GH5 GF6 GF1 GX7 GX85 E-M5 E-M10 E-M10II E-PL5 (not for EF-S mount lenses) 0.71x focal reduction converter: the focal length is multiplied by 0.71 according to the original (equivalent focal length = focal length x 0.71), which helps to enlarge the aperture by 1 stop Adjustable AF & Aperture Functions: Auto focus function, increase the lens by 1 f-stop and the amount of light on the virtual background, to better highlight the theme; adjust the aperture directly from the camera to control the actual aperture of the lens Material and design: the bayonets are made of metal with surface plating treatment, to be durable and sturdy; Built-in copper electronic contacts and IS function, which makes the focus precise and clear, with tripod foot with 1/4" thread at the bottom, etc. USB firmware upgrade: equipped with USB interface, can realize software update. It can refine new lens mount adapter functions and fix bugs based on subsequent updates