Frantix

Designed by Stewart Coffin (puzzle no. 9), made and sold by Interlocking Puzzles 2000.
(wood, 6 identical pieces and 6 corresponding identical pieces, 2.6 inches)

A variation of the 1890 Altekruse burr with pins and holes for some of the notches; shown on page 79 of the Coffin Book. Below are photos of one way for inserting pieces 3 through 11; piece 12 is then added to complete the two halves as shown above, which then slide together.