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21x23x1A – Merv 13

21x23x1A – Merv 13
AC Furnace Air Filter
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2 $0.00
3 $0.00
4-5 $0.00
6-11 $0.00
12+ $0.00

Product Description

Filter Size: 21x23x1A

Actual Size: 21x23x1

Actual Size Fraction : 21x23x1

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Shop 21x23x1A Air Filters Online

Custom Filters Direct is one of the leading names when it comes to purchasing 21x23x1A HVAC and furnace filters online. Our air filters are made with 100% synthetic material and are highly effective at eliminating almost all allergens present in your home or business environment.

By placing quality 21x23x1A air filters in your HVAC system, you not only remove the smaller particles but also eliminate the odor from the indoors and make your space fresh and clean. With a state-of-the-art design, these air filters do not absorb moisture and keep your HVAC system working efficiently. With this unique feature, your family will benefit from breathing in cleaner, safer, and healthier air.

Custom Filters Direct recommends you to change your air filters every 2-3 months. The dust and dirt particles keep accumulating on the surface over time and clog the pores of the filters. Keep in mind a dirty air filter can cause numerous problems for your health and the environment. Dirty air filters do not allow the clean air to pass through and increase your energy bills by creating unnecessary work for your heating and cooling systems.

Select The Right MERV Rating


MERV 8 filters suit most household settings. These air filters block 85% of particles between 3-10 microns in size.


MERV 11 air filters suit both residential and commercial environments. These air filters capture more than 85% of harmful particles 3.0-10.0 microns in size and 50% of 1.0-3.0 microns size particles.


These air filters provide enough level of filtration without hitting your wallet. These air filters immediately grab and trap 90% or more airborne contaminants between the size of 3.0-10.0 microns and up to 75% of 0.3-1.0 microns size particles.

21x23x1A Air Filters Delivery

Need to replace your dirty 21x23x1A air filters? Custom Filters Direct is your one-stop shop to buy the best 21x23x1A furnace and AC filters to meet all your air filtration needs. We offer a subscription service of filters, so you don’t have to worry about replacing your air filters on time. We also offer one-time delivery for our new customers to try our air filters. So, choose the option that suits your needs and place your order now! We also offer a huge discount on bulk orders of 21x23x1A filters