The discussion of the new "0.10" narrower RMS-C prompted the staff to do an updated study on optics for the Glock 43 system.
Most optics are narrow enough to fit, but too long. The width on a 43 is such that it will accept any optic with a 1.0" width...maybe a 1.10" depending on the location of the screws. But the factory slide, with its rear sight placement limits use of certain optics because they will intrude excessively into the firing pin safety hole. Since placing the rear sight forward of the optic is a poor idea, the location of that dovetail becomes an important factor if designing a Glock 43 slide
The RMR is too wide, but the Deltapoint is not, although the Deltapoint is too long.
We have fit the Vortex Venom (and thus a Fastfire fits as well), Docter, J-Point, Shield RMS. There may be others we have not tried.
Again, the limiting factor is the rear sight dovetail.
When we bring out our Suarez Signature Glock 43 slides, that will not be an issue and any red dot sight will be able to be mounted on the 43.