The O-ring I used was one I had on-hand that was a near ideal size.

It's outer diameter measures approx .903" (15/16" or 23mm) & is .116" thick (7/64" or 3mm).

I'm planning on going to Ace Hardware tomorrow to buy an extra one & I'll let you know what # O-ring it is.

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PS: I updated post #2 with pics of the O-rings (#14 & #57) that work. These are both 3/32" thick. The next thicker size is 1/8" & they are too thick.

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