Tapered hole major diameter is 3.500 inches , flow direction is from the outside in; cylindrical shape
NSN 5895-00-222-8555
NSN 5910-01-239-3997
NSN 5999-00-063-3246
NSN 6135-01-470-4077
NSN 6650-00-802-9833
NSN 5950-00-815-1739
NSN 5915-01-286-2158
NSN 5935-00-243-8752
NSN 6650-01-304-4955
NSN 6145-00-578-7522
NSN 5975-01-109-3003
NSN 6220-01-035-4350