Metric diameter US Knitting Needle Number Corresponding Crochet Hook Size 7000225000000000000 ♠ 2.25 mm 7000100000000000000 ♠ 1 B - 1 7000275000000000000 ♠ 2.75 mm 7000200000000000000 ♠ 2 C - 2 7000325000000000000 ♠ 3.25 mm 7000300000000000000 ♠ 3 D - 3 7000350000000000000 ♠ 3.5 mm 7000400000000000000 ♠ 4 E-4 7000375000000000000 ♠ 3.75 mm 7000500000000000000 ♠ 5 F - 5 7000400000000000000 ♠ 4 mm 7000600000000000000 ♠ 6 G - 6 7000450000000000000 ♠ 4.5 mm 7000700000000000000 ♠ 7 7 7000500000000000000 ♠ 5 mm 7000800000000000000 ♠ 8 H - 8 7000550000000000000 ♠ 5.5 mm 7000900000000000000 ♠ 9 I - 9 7000600000000000000 ♠ 6 mm 7001100000000000000 ♠ 10 J - 10 7000650000000000000 ♠ 6.5 mm 7001105000000000000 ♠ 10.5 K - 10.5 7000800000000000000 ♠ 8 mm 7001110000000000000 ♠ 11 L - 11 7000900000000000000 ♠ 9 mm 7001130000000000000 ♠ 13 M / N - 13 7001100000000000000 ♠ 10 mm 7001150000000000000 ♠ 15 N / P - 15 7001127500000000000 ♠ 12.75 mm 7001170000000000000 ♠ 17 -- 7001150000000000000 ♠ 15 mm 7001190000000000000 ♠ 19 P / Q 7001160000000000000 ♠ 16 mm -- Q 7001190000000000000 ♠ 19 mm 7001350000000000000 ♠ 35 7001250000000000000 ♠ 25 mm 7001500000000000000 ♠ 50 U
what letter is a size 4 crochet hook
E-4