U.s./canadian Transformersthese Transformers Have Straight Blade Pins And Are Designed Primarily For The U.s., Canada, And Mexico, As Well As Certain Other Countries, Such As Japan.cir-kit Plug-in Transformers Provide A Safe And Convenient Power Source For Any Dollhouse Or Miniature Room. All Cir-kit Concepts' Transformers Are Designed To Plug Directly Into A Powered Outlet, Thus Eliminating The Need Of Building A Special Transformer Enclosure Within The Dollhouse.cir-kit Dc Output Transformers Are A Marked Improvement Over Our Prior Ac Models. They Provide A Steady 12 Volt Output, Whereas The Ac Style Had A Higher Output Voltage With Light Loads And A Lower Voltage At Heavy Loads. The Higher Voltage Was Hard On Bulbs And The Lower Voltage Resulted In Dimmer Lights. The Dc Transformers Are Completely Solid State Allowing A Constant 12 Volts At All Load Levels. They Also Have Many Safety Features Including Short Circuit And Current Overload Protection. They Are Virtually Burn-out Proof. The All Electronic Design Also Results In A Much Improved Efficiency Over That Of Ac Versions.