40 Three-Dome Tank Car - TEXACO #7518 - HO Scale. Three Dome tank cars were popular in the early to mid 1900’s, as they were designed to haul a variety of oil’s and chemicals. Bachmann Three Dome Tank Cars, come in a variety of colors and road names. Each tank car is fully assembled and features; Highly Detailed Painted Bodies with Precision Graphics (where applicable), Blackened Machined Metal Wheels with RP 25 Contours, Magnetically Operated E-Z Mate Couplers, Non-magnetic Blackened Brass Axles with Needle-point Bearings, Celcon Trucks, and Added Weight for Optimum Tracking Performance