638 LEGO Lots of Extra Basic Bricks

LEGO Supplementaries were sets released during the early days of the LEGO system. These sets were designed to supplement and expand upon the building possibilities of existing LEGO sets. Instead of being complete stand-alone models or kits, Supplementaries provided additional bricks, special parts, wheels, windows, doors, gears, or even motors. These sets were especially useful during an era when LEGO's product line was simpler and less specialized than it is today.

Supplementaries consists of 75 sets that ran from 1973 to 1996. As of today, 637 Play Table is the most valuable Supplementaries set with an estimated new/factory sealed value of $266.