PART NO. THREAD O-RING DIMENSIONS E E A L S1 4F-04 9/16"X18 7.65X1.78 9.8 16.8 17 4F-06 11/16"X16 9.25X1.78 11.2 19.2 19 4F-08 13/16"X16 12.42X1.78 12.8 21.8 22 4F-10 1"X14 15.6X1.78 15.5 25.9 27 4F-12 1.3/16"X12 18.77X1.78 17 27.4 32 4F-16 1.7/16"X12 23.52X1.78 17.5 27.9 38 4F-20 1.11/16"X12 29.87X1.78 17.5 27.9 46 4F-24 2"X12 37.82X1.78 17.5 27.9 55