KRISS USA currently does not produce night sights. However, there are several aftermarket night sight solutions available for current production SPHINX models by several companies including XS Sights, Meprolight, Modern Weapon Systems, and ZR Tactical Solutions.
The rear sight dovetail is very similar to Novak specifications, however please note that the profile does differ slightly and fitment may be required. We are not able to provide direct assistance with regard to fitting aftermarket sights onto your SPHINX model.
KRISS USA currently does not produce an adapter to install optics, nor are we currently aware of any manufacturers that offer such an adapter. While we are aware of some SPHINX owners that have successfully milled the slide for optics, extreme care must be taken as the pocket where the firing pin safety is located is very close to the surface. If the slide is cut too deep, it will break in to this pocket. We are not able to provide exact measurements for this, nor do we offer services to mill the slide at our facility.