[FUNCTIONS & USES]--203368 Air Prefilter Replacement traps larger particles in your air to help improve overall indoor air quality. Honey-well air filter f50f helps to improve the efficiency of the air purifier,eliminating 90% of indoor dust particles and creating a fresh environment . This electronic air cleaner pre-filter is washable, and will only require replacement if it is damaged. [UPGRADE QUALITY]--The honey-well 203368 replacement prefilter is made of high quality aluminum materials. Polypropylene filters tests shows 43% increase in average arrestance efficiency over metal mesh prefilter. The commercial prefilter has an exclusive vinyl bonding process so the frame securely grips the mesh. Also the corners of the frame overlap adding more strength. The flimsy residential prefilter twists and flops when handled, the commercial version is ridged. [APPLICABLE MODELS]--203368 Air Prefilter Replacement for Honey-well Air Cleaner. Compatible model numbers includes Honey-well electronic air cleaner F300E1019, F300A1625, F50F1073, F50F, F300 etc, and will NOT fit the the F50A or F50E Series.This filter is designed to install in the 1/4 inch slot in your Honey-well electronic air cleaner cabinet. The prefilter is designed to protect the electronic cells in the air cleaner. Sold as a two-pack (2 prefilters are required per air cleaner). [CLEANING TIPS]--Clean your pre-filters every 2-4 months. Used pre-filters are very delicate and care should be used while cleaning them. Do not clean pre-filters in the dishwasher. Tap water from the sink or an outside hose should work fine. Do not whip or shake the pre-filters when drying as this could cause ripping. Always allow the pre-filters to dry before placing them back in the air cleaner. Colour:Silver Material:aluminum Package Contents: 2 x Air Prefilter Filter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.