1521 LEGO Basic Building Set Trial Size

The LEGO Universal Building Set theme, also often referred to as the 'Universal' theme, was a series of sets released primarily in the 1970s and 1980s. These sets were somewhat similar in concept to the LEGO Basic theme. The primary characteristic of the Universal Building Set theme was its emphasis on open-ended creativity. The sets didn't belong to any specific storyline or detailed theme, like castle or space. Instead, they provided a mix of basic bricks and some specialized pieces, allowing builders to create a wide variety of models from a single set.

Universal Building Set consists of 8 sets that ran from 1985 to 1991. As of today, 1512-2 Basic Set with Storage Case is the most valuable Universal Building Set set with an estimated new/factory sealed value of $554.