This solenoid unit is voltage specific for all of our mortise lock modifications. You will need to chose the brand name of the lock you have when ordering, since the cam is different for each of the locks we modify. Comes with our plug in bridge rectifier whip for AC/DC operation. Unit is available in 12 or 24 volt. If you need specific instructions on how to replace a solenoid in our Corbin Russwin, Sargent, Yale or Schlage modifications, you can click here for our video turtorials or here for our PDF instruction sheets.