Oasis All-Weather water bottles are heavy duty natural (translucent) polyethylene plastic bottles. These high quality PE bottles look good on any cage and are long lasting. Recommended for indoor or outdoor use - will last longer if protected from UV light. All-Weather bottles have a colorful silk screen design with a coordinating colorful angled cap. The drinking tube is high quality stainless steel with two heavy stainless steel balls in a ball-point tip and rubber gasket. 8 ounce size is suitable for hamsters pocket pets some reptiles baby rabbits and guinea pigs and for travel cages.