Difference between rancos?

Does anyone know if there is a major difference between the ranco 1110000 and the 1120000? Can they both be used the same?

O.k I found out they are the same except the 112 requires a 24vac input, but I don't know what that means....

Assuming you are using it in a house you want the 111 model.

edit...I should qualify this better. Assuming you are using Flexwat (or other over the counter heating pads) which are 120 volt you want the 111. 24VAC is used in low voltage but typically high amperage heating/cooling equipment like your AC or furnace.

Hope this helps.