The UCL lenses are here. The 51.3mm lens fits perfectly, 52.1 mm fits barely but does drop in without any pushing. Thicknesses of either are good.
Initial observation is that the coating makes the lens looks like it’s not there (same as what happens when eyeglasses are coated). It’s a strange (and beautiful) thing to see. As for the gain in brightness, testing for gain is more difficult as the gain is small and seems inconsistent; the result so far is at best *around 4*. Definitely, gain from AR coating is not nearly as large as the 15 gain of Samsung battery over Wurkkos battery.
If you are going to switch lenses, keep in mind there are two rubber rings: one below the lens “sitting” on reflector, and one above the lens “sitting” on bezel. Importantly, I have no way to confirm and not 100% sure, but it seems to me the one on the reflector is smaller. At least in my light, that’s the only way they fit nicely.
