AARGHHH!!! Once again bitten by mail order/Chinese(maybe)parts/part number cross. I ordered the Sierra version of the recommended quick coupler and got something like what was pictured in ad. first the barb is a 3/8 not a 1/4 or 5/16 shown. Next the knurling is different but that’s not a problem. They hook together(sort of)-no air flow though until I poked a skinny wire in the male end hmmmm? Thirdly the spring loaded sleeve doesn’t lock completely as the hex shoulder of the male 1/2 hits the female b4 the balls drop into the groove-poor dimensioning? And you can pull it apart due to partial locking. The flow issue is possibly due to the pair not seating all the way(perhaps 1-2mm but also the spring on the male’s ball check is weaker than the spring of the female’s center pin. I’m going to machine off a bit of the male hex in order for things to lock properly and if it still doesn’t flow I’ll try small tube extension on the pin. I hate sending parts back and haven’t gotten a reply from the vendor after sending message of issue. Anyone else ever dealt w Harvard Marine in N.Y.?

I was able to get it to work. I trimmed the hex shoulder so it locked but still had no flow. After several attempts at an extension for the pin decided the male 1/2 needed stronger spring. Found one in my spring drawer and now it works. A bit of a hassle but challenges are fun too.

I am a thrifty(cheap) Norwegian. Other folks had troubles even when they bought the pair. Not sure if it was Sierra fittings but I’ll bet they’re made in " The People’s Paradise". Here’s a shot of my mod.