10x33x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack Grow Light Reflectors Unlike consumer-grade units that struggle

Unlike consumer-grade units that struggle under continuous operation

Factory Calibrated: The PH-80 meter is factory calibration to pH 7

The Centurion QuanTanium wet tumbler allows the operator to process material when it's wet rather than Dry

Each paper is watermarked with our patented Criss-Cross watermark

as well Nutrient Scales including NaCl

10x33x1 Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack Grow Light Reflectors Unlike consumer-grade units that struggleNordic 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