5.5 mm Neoprene water bottle enclosure / cover. Includes plastic cage, allen key, screws washers. Winter Bot fits and encloses up to an average 20 ounce bottle and has enough room for a heat pack. Extended zipper pull for easy open close while riding with winter gloves. A normal water bottle freezes at 20 degrees in roughly 20 minutes while riding, so you can't get water out. This happens because of water slopping around and then the cap freezes up. It's no fun riding 30-40-50 miles without water. 5.5mm zippered neoprene bag encloses a nice bottle cage to keep a 20oz bottle from freezing Includes Plastic Cage, allen key, screws washers Extended zipper pull for easy open close while riding with winter gloves