Its function is now performed by the 1PN96MT-02 sight, which, in fact, was also planned for installation on old T-72 and T-80 tanks, but ultimately became the prerogative of the modernized T-62M. By itself, this sight is, in principle, self-sufficient in the sense that it can be used as the main one, albeit a very simple one.
He, unlike Sosny-U, does not have a daytime channel - only thermal imaging, but with a laser rangefinder. It is based on an uncooled matrix, which most directly affects the target detection range, which is approximately two to three kilometers. And this is significantly less than its predecessor.