This kit includes a replacement end cap gasket and a high-performance 400 micron internal filter for Facet Cylindrical ("Interrupter") Fuel Pumps.
The filter should be installed with the narrow opening facing towards the center of the pump. The wide opening should point towards the pump end cap.
Facet pump numbers 40053, 40220, and 480534 (Pegasus Part No. 1106) are originally supplied with this filter. The 400 micron filter flows more freely than the more common 74 Micron Cylindrical Pump Filter (Part No. FAC-479729), but it will let more particles through.
More information can be found in our Fluid Filter Micron Ratings and Recommendations Guide.