The Boss filter info states 15,000 mile protection when using fully synthetic oil only. The centre tube as well as the end caps appear to be the same across all lines. The bottom of the line premium mentions some 5,000 miles protection and at the same time meets normal manufacturers oil change intervals. A bit of contradiction with many normal OEM specs being up to 15,000 miles. 5,000 or 15,000 which is it? Their guarantee sides with the owner's manual as it should. I wish they would clarify what these 5,000 -10,000 -15,000 numbers mean. I think it's all marketing nonsense. They all have to meet OEM specs.