Gravity bag from old 2 L Platypus. PVC pipe pre-filter turned to snug fit to inside of platy spout (does not leak) and has a male pop bottle thread glued to lower end. Sawyer filter now screws on to pre-filter. Filter media is polyester fill rolled tightly and inserted into PVC with about 1 inch sticking out inside of bag for a course filter. Optional small bag of activated charcoal loads into bottom of pre-filter to improve taste. Water for testing was from turbid pond.
At home, another adapter from female pop bottle thread to garden hose allows quick back flush (at low pressure)
Total weight to service 2+ people is 8.6 oz.
