The O-ring is A1633-11 or PRP909-6; commonly made by Parker Seal Company.
Outside Diameter: .048
Length Under Flange: .096
Flange Diameter: .072
Wow, what can I say about this O-ring? It has everything you could possibly want! I mean, it is round, soft, fits in a groove, and seals out oil to prevent those nasty leaks! Ingenious! You should buy this today! Im so excited I want to buy more right now, but I think Ill wait until I actually need them again. (Seriously Aircraft Spruce? You really wanted me to review an o-ring?) :-)