American model companies who had been producing assembled promotional scale models of new automobiles each year for automobile dealers found a lucrative side business selling the unassembled parts of these "promos" to hobbyists to assemble, thus finding a new revenue stream for the injection molds which were so expensive to update each year. These early models were typically lower in detail than currently standard, with non-opening hoods and no engines, and simplified or no detail on the chassis, which attached to the body with very visible screws. Within a short time, the kit business began to overshadow the production of promos, and the level of accuracy and detail was raised to satisfy the demands of the marketplace.