Flange Locking: The adapter ring has a threaded flange-locking structure which is robust and reliable. The lens will not shake after installation Dust and Splash resistant: Dust and splash resistant design withstands use under harsh conditions for high mobility Matt Paint: To reduce the influence of external stray light on the imaging performance, there are extinction threads and matt paint inside of the adapter Focus to Infinity: Advanced CNC processing and professional assembly technology ensure product quality. The lenses will focus to infinity on your cameras Hard Anodizing: Aluminum alloy parts are anodized. Hard-anodized aluminum has good wear resistance and corrosion resistant