Just one word of caution...
Do not screw the filter onto the front of the lens hood. The filter will get stuck and it's placed too far off from the front lens element, hence will affect the image quality.
A customer came to me and said the lens was not sharp, until we nailed it down that he actually mounted the UVIR filter onto the front of the lens hood. As a result, when pixel peeping, the image wasn't as sharp as other copies.
Took out the filter and mounted it on the lens itself gave a 100% razor sharp image and he was a happy man again...