Koolance QD3-MSG4-BK QD3 Male Quick Disconnect No-Spill Coupling, Male Threaded G 1/4 BSPP *Black*

love them

First, keep in mind you must pair this with the Female version of the same size ( in this case Koolance QD3-FS10X16-BK QD3 ) and keep in mind your soft tube size (ID/OD) in my case this was ID=3/8" OD=5/8".these things are kind of on the expensive side, but they are all metal ( the others i found were plastic and reviews said they really didn't work to well after a few connect/disconnect actions ). These are industrial strength. I was planning to use them for all the connections in my loop ( because when draining a loop it kinda sucks to get water all over your pc and water and electricity are a bad combination ) however there is a drawback with these, they restrict water flow A LOT. So i used them for my drain tube and added one that i can blow air into to force all the water out of the loop and through the drain tube. I would highly recommend the Koolance QD3-MSG4-BK QD3 / and Koolance QD3-FS10X16-BK QD3 for this purpose.I'm subtracting one star because the Koolance did not discuss flow impendence which has a real impact on how much cooling you can get from your loop.

These are very convenient, but will fail over time. I have used them for years and I believe they are a good add on to your system.

Taking off a star because the black coating on these is garbage. I hand tighten, and then use a small wrench with a microfiber cloth between the jaws and the fittings, to make a slight snug quarter turn if that. Immediately I noticed the super thin black coating comes off. It may as well be spray paint.Great fitting, great company, but the paint job isn't great.Taking off 1/2 more star if I could, because these can be found on several other store fronts, with free shipping if you order over XYZ amount, for $14-$16. These need to be price dropped on Amazon.The remaining rating is given because these things are rock solid. I had them in my build for 5 years, and just reused them for the next one. I had fittings I hadn't taken apart in 5 years slightly stick and drip a few drops sure, but there's others I took part constantly while benchmarking GPS, and they work flawlessly.

If you've got the money to throw around, these are a super handy way to streamline your liquid cooling design. It makes repairs and replacement of tubing SUPER easy. If you need to isolate a pump or radiator, you can do so without having to purge and drain your system. I HIGHLY recommend these for major components. The compression fittings are superb and easy to mount, with the large, easily turned nuts. You can get them more than tight enough with finger compression.However, they ARE bulky. Expect to lose two inches of flex on any build. They work great for pumps and radiators, but you'd be very hard pressed to get them to fit a connection from CPU to VGA, for instance.