I use these, never had any issues with them: https://www.amazon.com/Aerostar-16x25x4-MERV-11-Pleated/dp/B01D94DAMS/ref=sr\_1\_8?crid=1KLYGTA8X5112&keywords=16x25x4&qid=1679751126&sprefix=16x25x4%2Caps%2C102&sr=8-8&th=1