The construction is "thin". The forks aren't that heavy duty but that isn't the problem. ...
Tactical MOLLE Hydration Pack Backpack 900D with 2L Leak-Proof Water Bladder, Keep Liquids Cool for Up to 4 Hours, Outdoor Daypack for Cycling, Hiking, Running, Climbing, Hunting, Black
Hydration Bladder 2 Liter,Pupet Water Bladder 2L Leakproof Water Reservoir Use for Cycling Running Climbing Hunting Hiking Camping Water Storage Bladder Bag
Hydration Bladder Water Reservoir 2 Liter 70 oz for Hiking, Camping, Cycling Backpack, Leak-proof, FDA Approved, Tasteless, BPA-Free and Large Opening Insulated Tube With Shutoff Valve