replying to Dave, Barb Villa wrote:
I just learned the VERY hard way that apparently there are TWO SIZES for a 3/8
compression cap...one is marked OS on the package the other IS. I was given
the OS one and had the same issue as you did(yup...12 years
later)...fortunately an old plumber friend arrived nearby and explained this
to me and gave me one of HIS IS ones...that had already been fitted with a
rubber disk which sealed off the outlet perfectly. Lots of time wasted in ALL
of the big box stores. Teflon tape is irrelevant. Someone posted that Home
Depot still sold these units with a rubber ring included in the cap. The
display at my nearby store showed that. NONE of the for sale inventory had it.
My plumber confirmed this is now the new "normal"...someone needs to let the
store personnel know...or the manufacturers to clarify. Could be that China
ran out of rubber?! DAYS of my life lost on this stupidity! Be sure to check
for OS versus IS on the package when you buy.

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replying to Barb Villa, Petrov wrote:
This was super helpful folks... Same issue the Tomahawk 3/8" compression cap
I got from the Home Depot. I put it on - not to over tighten and it just plain
old leaked. Then did the usual Internet search and found this forum and looked
for old rubber hose. Found some - fashioned a round disc and wedged it in the
cap. Threaded on the Cap and Rubber disc and no more leaks. Worked like a
charm! I guess the fella at Home Depot has not done done a job like this -
I'll have to write a review on their Website. Thanks All!

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