Atlas O 3002955 - Premier - Scale Test Car "Chessie System" #X4920

• Road Name: Chessie System
• Road Number: X4920
• Product Line: Premier
• Scale: O Scale
• System,: 3-Rail

Features:

• Metal Wheels and Axles
  
• Die-Cast 4-Wheel Trucks
  
• Operating Die-Cast Metal Couplers
  
• Colorful, Attractive Paint Schemes
  
• Fast-Angle Wheel Sets
  
• Needle-Point Axles
  
• 1:48 Scale Dimensions
  
• Operates On O-31 Curves (3-Rail)

Overview:

A scale test car is a type of railroad car in maintenance of way service. These cars serve the purpose of calibrating the scales used to weigh loaded railroad
cars. Scale test cars are of a precisely known weight so that the track scale can be calibrated against them. Scale test cars are also weighed for various
purposes, such as Axle Load Limits, and Customer Billing. Because the cars must be a precise weight, most of them did not have airbrakes due to the change
in weight from brake shoe wear. Due to the lack of brakes, these cars were to be put on the rear of the train.