This is a replacement filter made for S&B's CAI for 1999-2003 Tacomas and 4Runners. Measurements are provided in case it may fit your custom application. S&B's filters are made with silicone in all the places the competition uses Urethane rubber. The advantage is they won't crack, have exceptional tear strength and can handle temperatures up to 400° F.S&B's cotton Cleanable filters are an oiled 8 layer cotton filter media. They are easy to maintain with S&B's Precision II Cleaning Kit. It is recommended they be replaced after 10-15 cleanings depending on your conditions.