i read all the infomation i could find on the bhaf and the best price was carquest but they charge you for shipping because they dont stock it but the cummins dealer said 38. 00 but they want shipping too because they dont stock it and they are 50 miles away napa is about 25 miles but they dont stock it either but they dont charge for anything but the 48. 00 for the filter the web sight said napa was 37. 00 or so but here in northern michigan it was 48. bucks how do i get it less i tried to run it through a shop but it did no good plus i looked at the pictures and it is very large it does look like the hood closespretty tight plus how do you keep in place?also the napa place says it is for marine use what does that mean?