I bought a CD not knowing there is a diff between .max & 3DS. The model collection is truly awesome. A truly great bargain if your are considering a career or business. Here's what they say : http://www.deespona.com/ "All the models comes in 3dsmax format. If you dont use 3dsmax, use a max license to output to 3ds or dxf formats, then you can read the models in any other popular format." The model are various, from Highly detailed to low formeach of the 5000 models. Regards, Pack