The Kriega Hydrapak Reservoir Elite HD (Heavy Duty) 3L is made from ultra-durable, abrasion-resistant TPU with RF-welded seams for superior strength and elasticity. It is fully reversible for deep cleaning and drying. Compatible with all Kriega Backpacks. The Hydrafusion Tube Flexible drink tube insulates in hot weather and offers protection in tough conditions. It also comes with a Comet Bite Valve and Dust Cover Lightweight valve self seals after each sip and can be opened and locked with one hand to prevent leaks when not in use. The included dust cover protects the silicone bite valve from collecting dirt. It also offers the Plug-N-Play Connect System to easily disconnect the drink tube. An auto shut-off valve prevents leaking. You can also remove the reservoir from your pack easily for convenient refilling. It weighs a lightweight 170g and measures 370mm x 200mm.