Fits Honeywell® enviracaire models 8330c, 11500 (EV-15), 11502, 11520, 11525, 11526, 17200, 17210, 18150, 18155, 32182, 50150, 51500, 61500, 83160, 83161, 83169, and 83330. The HEPA filter is 99.97% effective at removing particles as small as 0.3 microns from the air that passes through the filter. It measures approximately 6 1/4 H x 9 1/4 ID x 14 1/2 OD and the Surround Seal TM filter technology prevents dirty air from leaking around the filter. For optimum performance, replace filter every 12 months. This is an aftermarket filter.