Platypus GravityWorks Push-Pull Cap Adapter

MEC description: "This adapter allows Platypus GravityWorks systems to filter and backflush directly with most hydration systems and Platypus bottles that have a push-pull cap."
I recommend this piece of equipment for adding functionality to a gravity water filter system.

I have the Platypus GravityWorks 4.0L Filter System and this adapter fits perfectly on Platypus push-pull caps which can be purchased separately or come with some Platypus bottles. I just take the dirty bag with me and I use it all the time with the 1- and 2-litre Platypus SoftBottles and can backflush filter when held upside down higher than dirty water bag. It doesn't leak.

At camp (and in transport), I leave it attached to the exit hose and use it like a tap, with the clamp on hose, to wash hands or to fill pots or bottles directly from hose, then put plug in to keep the end clean and no bugs (ear wigs!) crawl into the tube. You still have to clamp the hose off to stop water flow like usual.

I also use the white connector to fill my Camelbak hydration reservoir using water-filled softPlaty bottle with the blue funnel part attached or without, attached directly to gravity system exit tube, without having to remove bladder from backpack. Just pull bite valve off hydration tube and connect. The white adapter fits tight and if it is hard to remove from blue part, just place in cup of hot water to soften rubber. 

Tip: If no water comes out when filtering into Platy bottle with push-pull cap, make sure that you pulled the cap open after putting the blue funnel part on the cap, as it will close when you push it onto the cap. I am still surprised if there is no flow and exclaim, "oh oh, what's wrong?" before I realize that I am just a dodo brain and I didn't pull the cap open, even though I have used it a million times, lol.

Background

I have been using this sweet little adapter for about 5 years now. I leave it on the water exit tube when packing it up when I'm travelling so it keeps the end clean. Such a simple little thing that adds functionality to an essential piece of equipment for when you're out in the middle of nowhere or even in areas where there is an "iffy" water source at campsites.