A method of assembling a canister filter system, the method comprising: inserting a first filter component into a second filter component (step 502); and continuing the insertion until a first tab of either the first filter component or the second filter component contacts the other of the first filter component and the second filter component (step 504); wherein the first tab of either the first filter component or the second filter component slides into a first slot of the other of the first filter component or the second filter component (step 506); wherein the first tab slides upwardly in the first slot until the first tab reaches a ramp portion of the first slot (step 508); and wherein the first filter component or the second filter component is rotated, causing the first tab to slide along the ramp portion of the first slot until the first tab reaches a circumferential portion of the first slot, and causing the first filter component or the second filter component to contact a seal (step 510), and wherein the first filter component or the second filter component is rotated until the first tab reaches a stop or a detent notch (step 512); characterised by attaching the first filter component or the second filter component to a third filter component, providing a seal (step 516) such that a second tab of a third filter component is inserted into a second slot of the first filter component or the second filter component until the second tab reachs a ramp portion of the second slot (step 518); and rotating the first filter component or the second filter component until the second tab slides along the ramp portion of the second slot, reaches a circumferential portion of the second slot, and continues until the second tab reaches a second stop or a second detent notch (step 520); wherein the first tab slides upwardly or downwardly in the detent notch (step 514) and the second tab slides upwardly or downwardly in the second detent notch (step 522). inserting a first filter component into a second filter component (step 502); and continuing the insertion until a first tab of either the first filter component or the second filter component contacts the other of the first filter component and the second filter component (step 504); wherein the first tab of either the first filter component or the second filter component slides into a first slot of the other of the first filter component or the second filter component (step 506); wherein the first tab slides upwardly in the first slot until the first tab reaches a ramp portion of the first slot (step 508); and wherein the first filter component or the second filter component is rotated, causing the first tab to slide along the ramp portion of the first slot until the first tab reaches a circumferential portion of the first slot, and causing the first filter component or the second filter component to contact a seal (step 510), and wherein the first filter component or the second filter component is rotated until the first tab reaches a stop or a detent notch (step 512); characterised by attaching the first filter component or the second filter component to a third filter component, providing a seal (step 516) such that a second tab of a third filter component is inserted into a second slot of the first filter component or the second filter component until the second tab reachs a ramp portion of the second slot (step 518); and rotating the first filter component or the second filter component until the second tab slides along the ramp portion of the second slot, reaches a circumferential portion of the second slot, and continues until the second tab reaches a second stop or a second detent notch (step 520); wherein the first tab slides upwardly or downwardly in the detent notch (step 514) and the second tab slides upwardly or downwardly in the second detent notch (step 522). <EOS>