Four different sets to detail any HO Scale structure kit. Two sets are a standard design found on industrial or commercial buildings, two others are a fancy design used with hotels and apartment buildings. Of each pair, one is a basic set with ladders to roof and sidewalk, the other is an extender set, (each sold separately) to be added to the basic set. All sets provide parts for three floors. No soldering is required - all can be assembled using cyanoacrylate (CA) glue. Etched in .010" brass. Fire escapes are styled for use on industrial buildings.