Center Tubes
Purolator: Uses a metal center tube with 169 holes, each about 3/32” dia. The center tube does not extend all the way to the top of the filter element. ½” of filter element at the top of the filter is exposed without additional support beyond the center tube.
AAP: Identical to Purolator
NAPA: Spiral construction metal center tube, much more rigid than Purolator/AAP or Toyota. 52 holes, each about 5/32” diameter.
Toyota: Metal center tube with 153 holes, each approx 3/32” diameter.
