This Code 83 Snap Track straight track assortment includes two pieces each of 3/4 in., 1 1/4 in., 1 1/2 in., 2 in. and 2 1/2 inch sections. HO scale.The code of a piece of track is the height of the rail in thousandths of an inch. Code 83 rail is .083 inches high whereas Code 100 rail is .100 inches high. Atlas Code 83 has finer ties and rail than Code 100, making it more true to scale. Its brown ties are more prototypical than Code 100's black ties.Code 83 track can be used with Code 100 using Atlas' transition joiners (Atlas stock # 551).