P-T IWI will inlay a green tritium dot in a factory front sight on those little J-frames. They will alos inlay a green bar under the rear notch. I worked on a better, though more expensive, system with them where the front sight is milled off and a black blade is dovetailed in. You get a high visibility black front sight, with a dot, that is also a night sight. They even bead blast the sight plane for you.