16 3/8x21 1/2x1 Carrier Replacement Filter by Aerostar – Air Filters Delivered
Aerostar 16 3/8 x 21 1/2 x 1 MERV 8 Pleated Air Filter, AC Furnace Air Filter, 6 Pack - Walmart.com
Aerostar 16 3/8x21 1/2x1 MERV 11 Pleated Air Filter, AC Furnace Air Filter, 12 Pack (Actual Size: 16 1/2" x 21 1/2" x 3/4") - Amazon.com
Glasfloss 16-3/8 x 21-1/2 x 1 Air Filters (Case of 4), MERV 10, Pleated, Made in USA - Amazon.com
16-3/8 x 21-1/2 x 1 MERV 11 ( MPR 1000, FPR 7-8 ) Pleated 1" Air Filters for AC and Furnace. Case of 12. Exact Size: 16-3/8 x 21-1/2 x 3/4 - Walmart.com