This item is ordered by cm; inside diameter is 28.7
NSN 6650-00-160-4288
NSN 6240-00-122-6697
NSN 5905-00-101-1657
NSN 5960-00-113-4314
NSN 5835-00-244-4956
NSN 6130-01-033-1536
NSN 5999-01-116-3862
NSN 5925-01-646-7103
NSN 6105-01-333-7903
NSN 6105-01-607-0381
NSN 5985-01-649-9608
NSN 5935-01-607-6428