a conduit adapter comprising:

a cylindrical body having an overall outer diameter and an inner diameter, a first end contiguous with the outer diameter with a male conduit adapter portion just small enough to fit snugly inside the female end of the first round exhaust conduit and a second end having a female conduit adapter portion (404a) with a diameter just larger than the diameter of the male end of the second round exhaust conduit, to fit snugly over the male end of the second round exhaust conduit; and

a female threaded interface contiguous with the inner diameter; and

a removable filtering assembly comprising:

an outer adapter ring (502) externally threaded to engage the female threaded interface contiguous with the inner diameter of the conduit adapter above;

an inner support ring (503) concentric with the outer adapter ring and joined to the outer adapter ring by a plurality of support ribs (504), providing a substantially open annulus (505) between the outer adapter ring and the inner support ring; and

a lint filter element (201) formed of filter material (203) joined directly around the periphery of inner support ring (503);

wherein, with the secondary lint filter assembly joined between the ends of the first and second round exhaust conduits, the lint filter element traps lint escaping from the clothes dryer, and the open annulus provides a relatively unobstructed air passage around the lint filter should the lint filter become clogged.