Not quite dustproof!

I have the items in use now for several weeks. Light transmittance and color fastness of the filter is super. The photos are with and without filters indistinguishable (this should be so, since I use the filter exclusively for scratch protection).
Points deduction there, because again dust comes behind the filter. That's probably it, because the glass is pressed into the outer ring only and was not bonded or provided with a sealing ring.
Otherwise, I'm satisfied.