C&H Precision BUIS (Back Up Iron Sights) were specifically designed to be used with the OEM Optic Ready Slides and Direct Milled Slides.
LowWitness is defined as a BUIS (Back Up Iron Sights) that sits between .075″ to .100″ into the optic FOV (Field Of View) which is equivalent to lower 1/6 to lower 1/8.
True Co-Witness blocks half of your red dot visible window / FOV while Lower Third blocks one third of your visible window / FOV.
Red Dot Industry Experts believe Back Up Irons should not be a vision blocker and should be as low as possible but still useable if needed.
LowWitness® Back Up Iron Sight heights provide you the lowest usable sight height without being a vision blocker “Everything you need, nothing you don’t”
Mark H (verified owner) –
I agree with the other reviewer…. Sort of. The front sight is tall enough for a super low co-witness thru an RMRcc on a milled VP9SK, but the rear sight is .100-.110” too short. From some height measurements, the slide is that much lower in back on three VP9s examined . I replaced it with a taller rear from another source, and that works great. C&H should investigate this and spec a taller rear sight, as all of their many other products and services have been excellent.
Brad Adams (verified owner) –
Sights seem to be of good quality but they were entirely too low for my gun. I have a VP9 I had milled for an RMR. Installed these and they are unusable. They sit too low and are under my optic. They are not useable in my book. Too low.