In the first of two posts, Three Points of the Compass looks at two ways to fit a 28mm thread Sawyer Squeeze water filter to a 42mm neck HydraPak water bladder.
Many will be aware that lindal valve gas canisters can be expensive, while bayonet connector butane cartridges can be much more affordable. There is a cheap, tiny, copper transfer nozzle available for putting the contents of one, in to the other...
Three Points of the Compass 