Housed at Dover Public Library.
 
Especially when you try to match the gears to the brainteaser image on the card(s), this toy becomes great for problem-solving, logical reasoning, fine motor control, hand-eye coordination, and visual/geometric awareness, with the black and white side adding an extra challenge if you feel up for it. Additionally, it "doubles as a great fidget toy" (fatbrain toys, n.d.).