S size fits 2.00 - 3.00 mm knitting needles (7 pcs in a package).

M size fits 3.25 - 4.50 mm knitting needles (7 pcs in a package).

L size fits 5.00 - 6.50 mm knitting needles (7 pcs in a package).

XL size fits 7.00 - 12.00 mm knitting nedles (7 pcs in a package).