Originally this was a form of modelling undertaken because of the low cost involved. Card, a means of cutting and glue are all that is needed. Some models are 100% card, while others use items of other materials to reinforce the model. After World War II cardboard models were promoted by a number of model companies. One company, ERG (Bournemouth) Ltd. produced a book "Cardboard Rolling Stock and How to Build It" and Superquick are still well known for their range of printed and pre-cut kits.