|LEGO® → System → Architecture|
750 Hobby and Model Box is an Architecture set released in 1963. Included in this set was several sheets of graph paper custom made for LEGO bricks. That is because each grid on the paper corresponds exactly to 1x1 brick size. There was also a cardboard stock ruler that has 4 different scale measurements (2 per side). They are 1:25, 1:50, 1:100 and 1:200. They are used for measuring the scale of the building that is being built from the bricks. A booklet included lists some of the functions of the Architectural system used with these sets, and also shows the other Architectural sets available, as well as the spare parts packs that are part of this system.