This set features plastic construction and palstic parts

Semi-Tractors Feature: Diecast metal construction

Thousands of Cars with this Common Design Served North America for 4 Decades

They are designed for use with the Atlas 21st Century Track System

Here is a Kadee 6721 HO Scale New Haven 50' PS-1 Boxcar #40510

Broadway Limited 6677 HO NP EMD F7 A/B Diesel Locomotive Sound/DCC #6008A/6008B ProductID_12163321 This set features plastic constructionThis is a Broadway Limited 6677 HO Scale Northern Pacific EMD F7 A B Pine Tree Scheme Diesel Locomotive Paragon 4 Sound DC DCC #6008A 6008B. Unpowered B Unit. Paragon4 Sound & Control System Features: Operates in DC & DCC with improved DC speed control (use DCMaster for DC Sound), Built In extra capacitance to navigate imperfect track, Pro Lighting Mode offers individual control of all lights on model, Switcher Mode for precise low speed control,