You have two fuel filters. One is the 'primary' filter which is a fuel/water separator filter. The gizmos on the bottom of that filter are 1) a petcock you open to check for water/drain water and 2) a sensor that detects water in the fuel and provides an alert on the dash.
Your other filter (the one without the fittings on the bottom) is your secondary, 2 micron filter. So the primary gets the big stuff and the secondary filters down to 2 microns so that traps most anything else.
'07 Country Coach Allure 470 Siskiyou Summit #31578, Cummins ISL 425; 2014 Ford F150 toad; Air Force One Toad Brake.
Glen Allen, VA; Smith Mountain Lake, VA.