Puzzle:Brain Drain Block Shock

In 1969 Mattel, Inc. produced six brain-teaser dexterity puzzles in the "Brain Drain" series. Technically known as "planar polyform" puzzles, they are made up of inexpensive plastic pieces held in a tray. Based on sound geometric principles, they are difficult to assemble. Their near-psychedelic colors and designs place them squarely in the late-1960s.