An oil-based odor trap arrangement for a waterless urinal including (a) a bell trap tube received within a cavity situated in a lower portion of the waterless urinal, wherein one end of the tube is adapted to be removably attached to the cavity; and (b) a strainer having a body and defining a cap portion and an integrally attached ring portion extending axially away from the cap portion, wherein the strainer is adapted to be received onto an opposite end of the tube whereby the ring portion partially envelopes the tube thus forming a baffle configured to: 1) contain an oil-based substance between the ring portion and a wall of the cavity; 2) accommodate the flow of fluid from the urinal between the ring portion and the tube; and 3) direct the fluid into the tube.