This O Scale 2 Pack of Lamp Shades are wired with Long Lasting LED's. Perfect for over a loading door as shown in the picture....or any other Building Wall use. They don't build up heat when operating so they are good for any building material.*** These are LED's which last far longer than "micro bulbs" & they run cold with no excess heat buildup..... Low power consumption as wellOperating voltage = 3V, Current = 20mA , DC Only....also included are 2 resistors for operating at 12-16V if required to wire inlineTHESE COME FULLY PAINTED and Pre wired ready for you to LIGHT UP YOUR STRUCTURES / SCENES......Hole size in wall required for O = .16" ...Approx 1/2" projection off of building wall