THIS IS A CLASSIC WOODEN SIGNAL OR INTERLOCKING TOWER. THEY WERE USED WHEREVER TWO RAILROADS INTERSECTED OR MERGED. THEY WERE USED BY ALMOST ALL AMERICAN RAILROADS. THEY WERE BUILT FROM 1890 TO 1960. THE KIT IS INJECTION MOLDED IN GRAY STYRENE AND CAN BE ASSEMBLED IN ABOUT A HALF HOUR.