Rotation device is configured at the bottom of the body of a diaper changer so that the diaper changer is capable of rotating horizontally relative to the playard frame via the rotation device when mounting thereon. In combination with a light source having a characteristic output beam, the lens may provide highly stable, miniaturized mid-IR sources that deliver optical beams. A layer of conductive material is formed on the first layer of insulating material. The closure member and sealing member may cooperate to control fluid flow along a fluid conduit formed in a wellbore tubular.