PART NO. THREAD DIMENSIONS E F A B S1 5TB4-02SP R1/8"X28 G1/8"X28 18 20 16 5TB4-04SP R1/4"X19 G1/4"X19 22 20 19 5TB4-06SP R3/8"X19 G3/8"X19 25.5 23.5 24 5TB4-08SP R1/2"X14 G1/2"X14 31.5 27.5 30 5TB4-12SP R3/4"X14 G3/4"X14 32.5 31.5 33 5TB4-16SP R1"X11 G1"X11 42 37.5 41 5TB4-20SP R1.1/4"X11 G1.1/4"X11 45.5 40 48