Amazon has this Omega 91900 Plastic Creeper on sale for $25.71 (regularly $47.99). It features 300 Lbs. capacity with the length of 36 inches and the width of 16 inches.
One piece blow molded creeper that made out of HDPE plastic, light weight but strong. With its impact resistant, it gives an users extra comfort while laying on it. Features 6 multi-terrain swivel casters, which are industrial strength with oil, chemical, and grease resistant. With caster size of 3", it provides with the extra maneuverability