20_1/2x25_1/2x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack plant-support - Pyrex glass tube

- Pyrex glass tube

"I was skeptical about the internal pump but it works perfectly

Features PWM-controlled stator blade fans that are designed for high static pressure applications such as ducting

This concentrated organic spray works within hours of application and does not migrate through soil

3% Calcium and 1% Magnesium in a highly available form

20_1/2x25_1/2x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack plant-support - Pyrex glass tubeNordic Pure Custom MERV 13 Plus Carbon air filters are made based on the actual measurements so be sure to measure your current filter to get the EXACT dimensions before ordering. As with all Nordic Pure filters, the effective life of your filter depends on the environment in which you live. We recommend changing 1 and 2 filters every 30 90 days. Our 4, 5 and 6 inch thick filters could last up to 6 months. EXACT MEASUREMENT: Furnace and air condition