A device for selecting objects inserted as payment into a product or service dispenser through an insertion slot. The device includes a transport member provided with a recess for receiving one object at a time and conveying the object placed in said recess to a measurement section (ZM) where object compliance testing means are arranged. Said device further includes drive means for continuously and irreversibly moving the transport member along a path such that said recess is continuously moved from a starting position (P1) in which it communicates with said insertion slot to a final stand-by position (P2) via said measurement section (ZM). Said compliance testing means receive transport member movement sampling signals. The device is useful for dispensing services such as tickets for car parking or public transport and the like.