BOTTLE ONLY FOR PHOTO REFERENCE AND IS NOT INCLUDED Compatible with Hydroflask, Kleen Kanteen, Aquaflask, Kool, Hydr8. For best fit, measure the bottom diameter of your bottle with a ruler to see what boot size fits. It will fit if your bottle is the same diameter or slightly larger. Buyers are responsible for any return shipping fees. Protect your bottles against dents and scratches with our silicone boots. Silicone sleeve offers additional grip on different surfaces, keeping your bottle secure. Combine silicone boot with your favorite flask for unlimited color combinations. Size Options - Small 7.5cm boot generally for 18oz/22oz Bottles - Medium 9cm boot generally for 32oz/40oz Bottles 7.5cm Small - For Hydroflask 12-24oz - For standard mouth Hydroflask 32oz 9cm Medium - For wide mouth Hydroflask, Aquaflask, Kleen Kanteen, Kool, Hydr8 32oz & 40oz bottles To confirm the correct size, please measure the base diameter of your bottle.