moving gadget on a pachinko machine
A mechanical feature on a pachinko machine that moves or transforms during play to add visual excitement and affect gameplay. Rare term used mainly in pachinko contexts.
The moving gadget on this pachinko machine moves dramatically during a jackpot.
役物 is a broader term for any special feature or gadget on a pachinko machine; 可動役物 specifically refers to those that move.
Compound of 可動 (movable) and 役物 (gadget, feature), a term from pachinko parlance.