A baby jumper is a device that can be used by infants to exercise and play in. The original baby jumper consists of a hoop suspended by an elastic strap. More elaborate baby jumpers have a base made of hard plastic sitting in a frame and a suspended fabric seat with two leg holes, often with trays holding toys. The door jumpers lack the tray. There are also mobile play centers, which look very similar to baby jumpers, but which have wheels.
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