It is simple to use: hang

breathability

Secure mounting via 6 interchangeable and individually positionable Velcro straps for attachment to the top tube

while the lightweight and comfortable frames are made from eco-friendly recycled plastic

21 oz standard mouth surf Size:21 oz It is simple to use:Double insulated stainless steel, to banish lukewarm drinks forever Designed for everyday adventures, the 21 oz Standard Mouth bottle from Hydro Flask is their mid range and most versatile product. Small enough to fit in a rucksack side pocket or your cars bottle holder but carrying over 600 ml of liquid, the 21 oz insulated bottle is the perfect companion for your daily travels. Plus, since its made without BPA chemicals, you can keep re using it