To provide an AV board the depth of which is made thin by making the storage base of the AV board be openable/closable so as to reflect the height of an AV apparatus on the depth of the AV board when the storage base is stored.

In a structure, the storage base 8 is attached to the AV board 1. A through-hole 10 is arranged in a storage base side surface plate 9, and a unit 13 having a through-hole and a rotating function is inserted into the through-hole 10. A through-hole 12 is arranged in a storage base side surface plate 11 and a unit 16 having a rotating function is inserted into the through-hole 12. Grooves 14 and 15 for accommodating codes are arranged in supporters 6 and 7 so as to reach the unit 13 having the through-hole and the rotating function.