QUATRO, Brickipedia

LEGO QUATRO was a theme in preschool series introduced in 2004 and discontinued after 2006. It was designed for children age 1 to 3. QUATRO bricks, hence the name, are designed to be twice the dimensions of LEGO DUPLO bricks. The name "QUATRO" also signifies that the blocks are quadruple the dimensions of the traditional LEGO System blocks. QUATRO bricks are compatible with DUPLO and System bricks. These pieces were baby-friendly, and were specially designed to endure teething. In addition, they

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