Variflow 
Extended Surface Rigid Cell Filters
Ultrafine microglass paper media
Moisture resistant construction
Single, double, no header models
Metal and wood cell sides
Corrugated aluminum separators
High temp models up to 900F
Three efficiencies - 90-95%, 80-85% 60-65%

Variflow SC
Same construction as Variflow except less media

Variflow Compact Series
Extended Surface Rigid Filters -2", 4" deep
Ultrafine microglass paper 
Aluminized steel cell sides
Corrugated aluminum separators
High temperature operation up to 750F
Three efficiencies - 90-95%, 80-85%, 60-65%

Variflow II
Extended Surface Mini-Pleat Filters - 4" deep
Ultrafine microglass paper media
Die cut beverage board frame
Skip bead, mini-pleat adhesive separators
Low cost design
Three efficiencies - 90-95%, 80-85%, 60-65%

Vari+Plus
High Capacity Extended Surface Mini-Pleat Filters
Ultrafine microglass paper media
Moisture resistant construction
Continuous bead, mini-pleat adhesive separators
V-bank assembly of mini-pleat media packs
Large media area, low resistance
Five efficiencies - 98%, 95%, 85%, 65%, 95% DOP

Variflow II MC
Extended Surface Rigid Box Mini-Pleat Filters - 4" deep
Galvanized steel cell sides
13/16" header on air entering side
Skip bead, mini-pleat adhesive separators
90-95%, 60-65% efficiencies

Vari-Pak
Extended Surface Rigid Box Filters
Ultrafine high loft microglass media
Pleated construction w/ pleat stabilizers on sides
Galvanized steel cell sides
Box construction (no header) and header models
Four efficiencies - 90-95%, 80-85%, 60-65%, 50-55%

Vari-Pak Model S
Same construction as standard Vari-Pak filters, except made with dual layer, microfine synthetic media