The VW3AE0901 is an air-conditioning accessory designed for Altivar 61 Plus and Altivar 71 Plus floor-standing enclosures — specifically the version with separate air flows or the compact variant. It keeps the drive cabinet's internal temperature within operating range when ambient conditions would otherwise push it past the thermal limit.
This is the complete air-conditioning unit for the enclosure — not just a filter grille or fan tray. It mounts into the dedicated cutout on the Altivar floor-standing cabinet, so the kit is complete: no separate bracket or hardware run. Verify the enclosure variant (separate-air-flow vs. compact) before ordering, as the cutout pattern differs between the two.