Same great features as the popular 24 oz big mouth bottle but in a smaller more versatile 21 oz size wide mouth for fitting ice cubes and easy cleaning soft rubber valve easy to handle soft food grade plastic that wont absorb odors wide mouth screw top is big enough for ice cubes seals tight large soft poppet valve is easy on your teeth delivers excellent flow and seals tight easy to handle non slip shape smaller 21 oz capacity fits on full suspension frames in a jersey pocket or