Night sights with tritium lamps are too fragile for installation methods like hammers and punches. Maryland Gun Works designed their sight tools specifically for but not limited to night sights. Beware of imitators, some designs are made to attempt to work on many different models but these individual tools are much better suited for their specific task.
"Tool is not designed to remove extremely tight factory rear sights. Sight tool is intended to install and adjust Tritium Night Sights"