Design, copyright, and 3D print by J. A. Storer, 2022.
(plastic, 3 x 4 x 3/8 inches, with cardboard sleeve)

Remove the black keeper and then slide the pieces to exchange DIVE and FISH; it can be done in 36 rectilinear moves. Motivated by the small size of the Ride or Walk puzzle and the "bridge" of the Work or Golf Abridged puzzle, this puzzle has a single fixed square, a free moving square, and the two I's are connected (forcing them to move only left and right in lock-step).