To solve a problem that obstacle of shortening in a machine width direction is constituted since a lifting base is required in every one pool conveyor in one track in a constitution for boxing and feeding out an agricultural product in a product box on the lifting base arranged at a side of the pool conveyor in one track by manual work.

A lifting base device 10 in which two lifting bases 11, 12 are arranged in a vertical row at the side of the pool conveyor 3, and a product box feeding out conveyor 21 extending toward a product box conveying conveyor 24 is provided on a lower part of the lifting base device 10. In the state that the front second lifting base 12 is stopped at an upper boxing position, height at that the product box 13 transferred from the first lifting base 11 to the product box feeding out conveyor 21 can pass is ensured between the second lifting base 12 and the product box feeding out conveyor 21, and the product box of the first lifting base can be fed out to the product box conveying conveyor 24 without being affected by the boxing work on the second lifting base 12.