Kootenay Filter Pre-Filter 500SL | Air Filter Replacement Light Meters + PAR Meters Then it holds off until

Then it holds off until humidity climbs 5% again

and no spare parts to stock

Valve Options: Normally Closed and Normally Open options are available for various sizes

Read the number the right way and this part is easy

If the probe is contaminated (dirty)

Kootenay Filter Pre-Filter 500SL | Air Filter Replacement Light Meters + PAR Meters Then it holds off untilExtend Filter Life with the Kootenay 500SL Air Filter Replacement Designed for SL500 filters without a flange, the Kootenay Filter Pre Filter 500SL blocks dust, debris, and larger particulates from reaching and clogging your primary filter. This replacement pre filter enhances air filtration efficiency, supports odor control, and reduces system maintenance over time. With a 16'' diameter, 20'' length, and compatibility with 6'', 8'', and 10'' flanges,