Size guide

INTERNAL DIAMETER IN MM	US	UK	EUROPE	BRAZIL
15.1	4.25	1	46.5	10
15.4	4.75	I 1/2	48.5	11
15.75	5	J 1/2	49	12
16.1	5.25	K 1/2	50.5	13
16.3	5.75	L	51	13.5
16.4			51.5	14
16.5	6	L 1/2	52	14
16.75		M		15
16.9	6.5	M 1/2	53	15.5
17.15	6.75	N	53.5	16
17.3	7	N 1/2	54	16.5
17.5	7.25	O	55	17
17.9		P	56	18
18.2	8	P 1/2	57	19
18.5	8.5	Q 1/2	58	20
18.8		R	59	21
19	9	R 1/2	59.5	21.5
19.2		S	60	22
19.4	9.5	S 1/2	61	22.5
19.6		T		23
19.8	10	T 1/2	62	24
20		U	62.5	24.5
20.2	10.5	U 1/2	63	25
20.4		V	64	25.5
20.6	11	V 1/2	64.5	26
20.9			65.5	27

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