The prototype of the car was built by the Thrall Car Manufacturing Company for the Southern Railway from 3-5/1971 (Series 994100-994199) This HO 1:87 Thrall M-200 MOW Ballast Hopper STL files comes with the early and later version body, barcode pad if needed, brake wheel and coupler box covers. The only thing you need to complete this model is some 100-Ton rolling bearing trucks with 33' metal wheels and metal couplers of your choice. Also you need 2-56 x 1/4 phillips pan head screws for the trucks and 2-56 x 1/8 phillips pan head screws for the coupler boxes. Note these STL files is for personal use only and not to be commercially reproduced!!!