Received these today and were immediately impressed by the quality and light weight. Very obvious that a lot of thought has gone into the design. Whilst not 100% waterproof, the packing cubes can be used for a wide range of applications. When travelling on dive expeditions I am always looking for light weight options to organise all my non-dive gear, given the outright weight of dive gear. Problem solved. When used in conjunction with a pack liner, the packing cubes provide a practical way to organise loose items, clothing, first aid kit, etc. within a hiking pack. Wish I had them on the Larapinta Trail. Solid zips and ergonomically located pulling tabs make it very easy to open and close, especially in low light conditions. Solid design, will add more to my kit.