canon g5 mounting ring for the ML-3, MR-14EX or MT-24EX to most lenses with 58mm filter thread., Make CanonThe CAN55-9291 Macro Lite Adapter 58C allows connection of the Ring Lite to most the camera lens filter 58mm specifications thread
It works perfectly, you can use a filter and UV lamps are mounted ring to add to their 100mm macro. I also bought an extra can, as fast as light ring MR-EX14 50mm f/1.4 mounted on my **** **** you
Due to the nature of the focus of 50 mm f / 1.4, the front of the lens moves in and out of the circle of light to heavy, and will aim to cause a malfunction and should be sent to Canon AF calibration .

It works fine without vignetting at 17-85, 28 mm f / 1.8 on a crop sensor with excellent results and the 70-200 f/4.0. Works great for the macro lens, of course.