Sea to Summit-pack-pack tap 4l-

 Hang this from a tree at the campsite and you have bulk water  literally on tap! Multiple durable lash points allow you to hang or  secure the Pack Tap™ in many spots. They can be rolled and squeezed into  tight spaces and with the use of 300D polyester for the exterior they  have a high abrasion resistance. A double layer tough Mylar bladder  holds your water (or wine) safely and the unit can be easily operated  with one hand.