base to enable fluid to flow bi directionally according to applicational specifications the unitary structural attachment plate 4 7 has an internally threaded center opening 9 an o ring groove 5 a peripheral lip surface area 20 and a plurality of circumferential fluid flow openings 8 that serve as flow ports whereby fluid to be filtered is distributed and circulated in a flow path appropriate to the internal filter element design and location within the housing the precise number of fluid openings and spacing therebetween are not critical to the practice of the invention the unitary spin on filter housing 1 4 7 16 is constructed by folding 23 the open end of the can 1 16 inward over the peripheral lip surface area 20 of attachment plate 4 7 and circumferential welding 22 the folded 23 tube wall 1 in the same appropriate method and manner as described heretofore for the construction of the can 1 16 the integrating connections between tube wall 1 and structural endcap 16 and the connection between the can 1 16 and the unitary attachment plate 4 7 comprise a critical feature of the present invention a filter element assembly is positioned inside the unitary filter housing 1 4 7 16 the element assembly comprises an o ring 10 an endcap 11 having a center opening to receive a portion of.