16_1/2x21x1 Exact MERV 12 Plus Carbon AC Furnace Filters 6 Pack Grow Strong Clay Pebbles size 4mm-20mm

Clay Pebbles size 4mm-20mm

while elastic wrists and ankles keep coveralls secure and in place

Elements Grow is a high nitrogen formula developed to encourage vigorous stem and leaf growth

In effect it defies gravity

Producing very high levels of PPF output of 816 µmol/s and a Photon Efficacy (fixture efficiency) of 2

16_1/2x21x1 Exact MERV 12 Plus Carbon AC Furnace Filters 6 Pack Grow Strong Clay Pebbles size 4mm-20mmNordic Pure Custom MERV 12 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