12x24x36 Koch Multi-Sak Extended-Surface Microfiberglass Filter, MERV 11 – 216-103-236 (6 Filters)

Description

This 12″ × 24″ × 36″ Koch Multi-Sak Microfiberglass Extended Surface Bag filter (part number 216-103-236) is a commercial extended-surface bag filter rated MERV 11, designed for commercial and industrial air handlers operating at face velocities from 500 to 3000 CFM.

What makes a bag filter different

Extended-surface bag (or pocket) filters use multiple deep media pockets instead of a flat pleated pack. The result is dramatically more filter surface area in the same footprint — typically 10–20× what a panel filter provides — which means higher dust-holding capacity, longer service life, and lower average pressure drop. They’re the workhorse filter in most large commercial air handlers.

Media and construction

• Media: Microfiberglass bag media for high-efficiency MERV 11–14 performance. Progressively loaded from upstream to downstream for balanced dust capture.
• Pocket construction: Rigid support members maintain pocket shape through the filter’s service life, preventing collapse under loading.
• Frame: Galvanized steel header (single or double) for standard side-access housings.
• Rating: MERV 11 per ASHRAE 52.2.

What MERV 11 captures

Fine dust, pollen, pet dander, mold spores, smoke particles, and smaller allergens. MERV 11 is the standard recommendation for households with allergies, asthma, or pets, and is commonly specified for commercial office spaces where indoor air quality is a priority. Confirm your system can handle the slight increase in static pressure compared to MERV 8.

Typical applications

Commercial office-building air handlers, school HVAC, retail, hospitality, light industrial ventilation, and as high-efficiency final filters in multi-stage systems.

Also worth considering

Shopping on price? Our house brand PrimeShield Advanced (MERV 11) covers the same efficiency tier across common residential and commercial sizes and is usually the better value. Choose this branded option when your equipment spec sheet or facilities team calls for it specifically.

Questions on fit, quantity, or a commercial quote?

Need a size that isn’t listed, a different pack count, or a quote for a commercial order? Get in touch — we handle facilities and commercial orders daily and can usually match or beat distributor pricing.

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