The FanTastic Fan 1250 Vent Upgrade Kit you've been looking for! FanTastic 801258 / 801259 Off-White Upgrade Kit for a previously purchased FanTastic Vent Fan. FanTastic Fan 1250 kit includes a Pop 'N Lock screen, a new interior assembly, and 3-speed and reverses airflow switches completely pre-wired. Upgrades are existing FanTastic Vent to a 4000R. To replace and upgrade to an old vent, install this upgrade kit into the existing opening. Get the best RV parts and RV accessories from a trusted and dedicated source.