Tapered hole major diameter is 3.500 inches , flow direction is from the outside in; cylindrical shape
NSN 5915-01-490-0244
NSN 5855-01-268-6468
NSN 5950-01-235-1249
NSN 5925-00-222-8263
NSN 5996-01-641-7919
NSN 5996-00-199-0073
NSN 2925-01-318-8853
NSN 5975-01-237-4256
NSN 6650-01-614-0947
NSN 6645-01-163-6144
NSN 6105-00-527-2193
NSN 5960-01-528-1147