A track follower (1226a, b) extending from said cover for insertion into said longitudinal track to provide slidable moveable of said cover within said track, said track follower having a frictional fit in said track to provide frictional resistance to the movement of said slidable cover along said track for retention of said cover in any operator selected position when said handle is removed from said holder, and opposed outside cover edges for frictional contact with said opposed flanges (1218a, 1218b) for frictional resistance to the movement of said cover on handle when said handle is within said holder for the retention of said cover in any operator selected position, such that said handle is releasable from said holder for dipping said collection absorbent into liquid specimen.
