Abstract: A fluid filter including a filter body having inlet and outlet passages communicating with an open ended chamber on opposite sides of a tapered seat area. A cupshaped fluid filter or strainer element is located in the chamber through the open end thereof and is adapted to be closely received in the seat area. A bonnet assembly covers the open end of the chamber, is threadedly mounted to the body and is comprised of a bonnet, a bonnet nut and biasing means. The biasing means is employed to exert a biasing force against the filter or strainer element to continuously urge it toward the seat area. At least the bonnet and bonnet nut are themselves interconnected in a manner that permits both rotational and limited axial movement therebetween. The disclosed structure facilitates access to the chamber and filter or strainer element without the necessity for removing the entire fluid filter structure from a service installation.