The AOI AD-M67-03 is the adapter for M67 Threaded Ports. It is a vital piece of accessory that will allow you to snap on a macro dioptre in front of your port, giving you a quick and easy fix to your macro lens. The retainer ring wrench is a handy and efficient accessory to tag along with your macro lenses as it will fasten onto most 67mm threaded ports or with most 67mm macro lenses.