NPS	D(outer dimension)	O(Center to Center)	K(Back to Face)
1″	33.4	51	41
1 1/4″	42.2	64	52
1 1/2″	48.3	76	62
2″	60.3	102	81
2 1/2″	73	127	100
3″	88.9	152	121
3 1/2″	101.6	178	140
4″	114.3	203	159
5″	141.3	254	197
6″	168.3	305	237
8″	219.1	406	313
10″	273	508	391
12″	323.8	610	467
14″	355.6	711	533
16″	406.4	813	610
18″	457	914	686
20″	508	1016	762
22″	559	1118	838
24″	610	1219	914