Jumbo Bricks was a small theme exclusively manufactured by Samsonite from 1964 to 1972. The sets contained bricks larger than the normal system bricks, much the same as today's DUPLO bricks. However, unlike DUPLO, Jumbo Bricks are not to a relative scale to standard LEGO bricks. They were marketed towards children from nursery school through to first grade. There were six sets produced for this theme.
1969 LEGO Sets
By 1969, LEGO’s continued international expansion and rising sales had increased its workforce in Billund to 843 employees. This year, LEGO revisited the concept of preschool building blocks and developed the fully compatible DUPLO System. Aimed at children from infancy to six years old, DUPLO opened a new market for LEGO, expanding its product offerings beyond traditional construction toys. The name "DUPLO" was derived from the Latin word duplex, meaning "double," as DUPLO bricks were twice the size of standard LEGO bricks in all dimensions. While LEGO pioneered this new system, in the U.S., Samsonite had already entered this market with its Jumbo Bricks in previous years.