This water bottle sleeve attaches to the shoulder strap of any backpack with webbing running down the strap (daisy chain). It uses two plastic siamese clips to attach to the strap above and below the pouch. It can then be cinched tight using the webbing slider on the back panel.
This water bottle sleeve comes in 2 sizes, a 0.7 liter smart water bottle, and 1 liter smart water. The weights of these are 1.3 and 1.4 oz respectively.
If you are ordering this for a backpack you already have (not for one of ours) please type into the notes box what kind of backpack you have so that we can make sure the attachment system will work well for you.