Super easy to use!
The GravityWorks is very easy to use and maintain. I filled up the bag from the lake, hung the filter in a tree, and walked away. It filtered the 4 liters in minutes. And I loved that I didn't have to pump anything! I came back and filled up my Nalgene with no effort whenever I was thirsty. Definitely a must have for any backpacker or camper camping near water.