The filter sits beautifully on the Sigma 100-400 lens and works fine. It also protects my lens from dust.
27.02.2019
Works just great. Note that this filter rotates so that you can have it vertically or horizontally. This is done via the front knurled ring but you could easily turn this thinking you were screwing the filter into the thread on your lens. This could lead to the filter falling off. So the back ring is for tightening and the front ring is for rotating. I have no issues with this filter and would happily by more from this range. I am using it on an expensive camera with quality lens and see no degradation in image quality.
14.09.2017
I haven't had the opportunity to use it yet but it fits my camera and appears to be ideal for my requirements
17.07.2017
K&F is example of good stuff for more than beginners. High quality, well made, good in use. You can really do a lot of more crazy stuff with them to your camera. Items were well packed, delivered very fast. Full satisfaction. Recommend!
21.05.2017
Awesome quality and cheap in price as I'm a photographer you get through these scratching them etc
31.01.2017