According to this needle measure tool, a 3.0 would be a US size 3 [3 1/8 mm] and a US size 4 [3 1/2 mm]. Thus, a 3.0 mm would actually be a 3 1/8 mm hook.
Remember the thickness of yarn and your tension when knitting also determines size of item.
According to this needle measure tool, a 3.0 would be a US size 3 [3 1/8 mm] and a US size 4 [3 1/2 mm]. Thus, a 3.0 mm would actually be a 3 1/8 mm hook.
Remember the thickness of yarn and your tension when knitting also determines size of item.