Sizing Charts

Inside Diameter (inches)	Inside Diameter (mm)	Inside Circumference (inches)	Inside Circumference (mm)	USA & Canada	British, Irish, Australian & New Zealand	European
0.458	11.6	1.438	36.5
0.466	11.8	1.463	37.2
0.474	12	1.488	37.8		A
0.482	12.2	1.513	38.4		A 1/2
0.49	12.4	1.539	39.1	1	B
0.498	12.6	1.564	39.7	1 1/4	B 1/2
0.506	12.9	1.589	40.4	1 1/2	C
0.514	13.1	1.614	41	1 3/4	C 1/2
0.522	13.3	1.639	41.6	2	D	1.5
0.53	13.5	1.664	42.3	2 1/4	D 1/2
0.538	13.7	1.689	42.9	2 1/2	E	2.75
0.546	13.9	1.714	43.5	2 3/4	E 1/2
0.554	14.1	1.74	44.2	3	F	4
0.562	14.3	1.765	44.8	3 1/4	F 1/2	5.25
0.57	14.5	1.79	45.5	3 1/2	G
0.578	14.7	1.815	46.1	3 3/4	G 1/2	6.5
0.586	14.9	1.84	46.7	4	H
0.594	15.1	1.865	47.4	4 1/4	H 1/2	7.75
0.602	15.3	1.89	48	4 1/2	I
0.61	15.5	1.915	48.7	4 3/4	J	9
0.618	15.7	1.941	49.3	5	J 1/2
0.626	15.9	1.966	49.9	5 1/4	K	10
0.634	16.1	1.991	50.6	5 1/2	K 1/2
0.642	16.3	2.016	51.2	5 3/4	L	11.75
0.65	16.5	2.041	51.8	6	L 1/2	12.75
0.658	16.7	2.066	52.5	6 1/4	M	12.75
0.666	16.9	2.091	53.1	6 1/2	M 1/2	14
0.674	17.1	2.116	53.8	6 3/4	N
0.682	17.3	2.141	54.4	7	N 1/2	15.25
0.69	17.5	2.167	55	7 1/4	O
0.698	17.7	2.192	55.7	7 1/2	O 1/2	16.5
0.706	17.9	2.217	56.3	7 3/4	P
0.714	18.1	2.242	56.9	8	P 1/2	17.75
0.722	18.3	2.267	57.6	8 1/4	Q
0.73	18.5	2.292	58.2	8 1/2	Q 1/2
0.738	18.7	2.317	58.9	8 3/4	R	19
0.746	18.9	2.342	59.5	9	R 1/2
0.754	19.2	2.368	60.1	9 1/4	S	20.25
0.762	19.4	2.393	60.8	9 1/2	S 1/2
0.77	19.6	2.418	61.4	9 3/4	T	21.5
0.778	19.8	2.443	62.1	10	T 1/2
0.786	20	2.468	62.7	10 1/4	U
0.794	20.2	2.493	63.3	10 1/2	U 1/2	22.75
0.802	20.4	2.518	64	10.3/4	V
0.81	20.6	2.543	64.6	11	V 1/2
0.818	20.8	2.569	65.2	11 1/4	W	25
0.826	21	2.594	65.9	11 1/2	W 1/2
0.834	21.2	2.619	66.5	11 3/4	X
0.842	21.4	2.644	67.2	12	X 1/2	27.5
0.85	21.6	2.669	67.8	12 1/4	Y
0.858	21.8	2.694	68.4	12 1/2	Z	28.75
0.866	22	2.719	69.1	12 3/4	Z 1/2
0.874	22.2	2.744	69.7	13
0.882	22.4	2.769	70.3	13 1/4	Z1
0.89	22.6	2.795	71	13 1/2
0.898	22.8	2.82	71.6	13 3/4	Z2
0.906	23	2.845	72.3	14	Z3
0.914	23.2	2.87	72.9	14 1/4
0.922	23.4	2.895	73.5	14 1/2	Z4
0.93	23.6	2.92	74.2	14 3/4
0.938	23.8	2.945	74.8	15
0.946	24	2.97	75.4	15 1/4
0.954	24.2	2.996	76.1	15 1/2
0.962	24.4	3.021	76.7	15 3/4
0.97	24.6	3.046	77.4	16

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