Permatron air cleaner upgrade kit includes:
(Qty 1) Electrostatic pre-filter
(Qty 3) Activated carbon post-filter
Designed specifically for the White-Rodgers or Electro-Air 20 x 21 air cleaner. Each filter measures 20¼ x 21 x 5/16". This upgrade kit is for all models SST1600, SST-16, 16C26S-xxxx, 16C27S-xxxx, UST.
These filters are the full size of the air cleaner and not split in pairs like the original White-Rodgers filters. One Permatron prefilter replaces the pair of original half size F825-0337 prefilters.
Also one permatron carbon filter replaces a pair of the F825-0468 carbon filters. These Permatron filters simply side right in and do not require clips as with White-Rodgers carbon filters.