Flanders EZ Flow Nested 4 Pack Panel Filter, MERV 1, 20" X 20" X 1"

Self-retaining spun glass media adheres directly to frame
Heavy one-piece chipboard frame protects against corner separation
Low initial pressure drop for energy efficiency
MERV 1 rating
Lasts up to 30 days
UL Classified

This style of panel filter has protected furnaces and air conditioners around the world for over 50 years. The media is made of continuous filament spun glass. Filters should be changed monthly in periods of high use.