OEMTOOLS 26133 High Flow 7 Piece Coupler and Plug Kit, 1/4" Body, 3/8" NPT, Quick Connect Air Hose Fittings, Air Tool Fittings, High Flow Air Fittings

first the coupler:For a non-safety style coupler, I love these. They can be found for better pricing elsewhere if you need bulk, but the oring is easily accessed to replace it (all of these V-style/high flow couplers have an oring wear item (I've tested about 10 different mfrs). I haven't nailed down the exact replacement though)Good quality vs price, I like the green color and the high flow etching to make sure they're not confused with other hardware flowing around, the knurling on the pull ring provides a good grip. They just feel good in the hand. They're also easy to disassemble down the road when the second oring wears.In initial testing while new, these seem to leak less with non-HF fittings (industrial/M style) than most of the competition.next the fittings:the quality on these is not as great - they're OK, but the chrome on some of them is flaking in spots, particularly where it wraps around the openings. prevost/milton/etc are better quality for often better price. but if you get them cheap enough, they're decent enough.

This set is awesome. First it is very complete and for the work I was doing, I needed multiples. The best part is the way they connect. The green sleeve stays back and you just PUSH the male end in..CLick...sealed. No wrestling with the collar and trying to get it to grab. I needed more and ordered the same because they work so well. My hoses, my compressors...all have this couplers now.

Looks like they will flow well. I didn't catch that the fitting is 3/8 on both sides, my error, so this will only be used gor select tools/hoses.

I bought two sets of these in March 2019, 6 months on and every single one of the 6 couplers has now broken, I had the same problem that has been reported here many times. The couplers work fine for the first few days, then when you remove a tool they will start to leak air, the ridiculous hard plastic seal cracks at first. One more insertion of a tool and the plastic seal completely breaks and the air hose starts to free-flow air. I have now bought the Flex-Zilla couplers, I should have done this in the first place.

These just arrived and I noticed right away the inner diameter didn't look as open as other Hi Flow "green zilla" connectors I have. See my pics for reference, smaller i.d oemtools 3/8 on the right, wide open 1/4 "zilla" on the left.I thought is was just my eyes ...so I pulled out my OriginCal calipers and measured the inner diameter .These measure 0.259" inner diameter ...while other couplers and ends from the big "green" zilla brand I have measured 0.291" . One might think this is not that much...and on nail guns and tools that don't need constant flow, it's probably true, but the reason we are buying "Hi Flow" couplers is because some tools performance are highly dependent not only pressure but on "Hi Flow" being there. Things link automotive impact guns and air ratchets. This might be the difference in having to first "muscle" free each bolt before running it off with air tools. In their defense, they are about 25% more "open" than standard air hose ends, but they are visibly smaller than green "zilla" brand. If you're not running automotive air tools and tools that need torque and constant flow, these are probably fine, for nail guns this WONT matter. They are about the same money and will have better flow than standard air end connectors. But say you've got a 70 Ft/lb air ratchet...or maybe a pneumatic impact gun...if you want to get the full torque out of them, you want them to muscle off bolts saving time, then get the most "Hi Flow" air ends you can get. On a side note, I also ordered milton "Hi Flow" ends (3/8 NPT part# s-763-1) thinking they would be good...but they too measure 0.260" inner diameter . So, to sum it up, the gimmick "green zilla" brand hi flow ends are the most open. Hope this helps others make a more informed decision . note: I didn't have a loose 3/8 flecks zilla connector to show so I used a 1/4" flecks zila ..but the part that plugs in is the same size, even though the thread is different.

Used these to set up a small shop's air system. these don't appear to be quite as high flow as some other brands, but for the price, they are hard to beat, and they look and fit great!

Really like these, the way they "click" and un-click. Had to force myself to spend the money, very glad I did.Oh, and they ARE "backwards compatible" with the old style. At least in the "fat coupler" to "narrow hose" direction, which is all you need. Very nifty.

The couplers are great, however... the plugs, compared to some competitors, have a smaller opening. But this could be fixed with eversoslightly boring out the plugs since there is plenty of material to work with as these are more heavy duty than some others available...