28mm Water Filter Adapter With Vent

28mm water filter adapter that fits most popular water filters used by day hikers, backpackers and thru-hikers alike.  If you are using a filter with a water collection bag and then attach it to a bottle, you will have to stop and let air out to equalize the air in both water collection devices.  With this adapter designed by Neutron Components Ltd, you no longer have to do that.  You can secure both ends and filter with no issues.  Just make sure the arrow on the adapter matches up with the flow on the filter and you will save lots of time on the trail filtering water.  These are 3D printed using PLA for all but the Blue Glow-in-the-dark, it is PETG.