The pattern calls for 4.0mm which is referenced as a US6 needle set. The needles I have at US6 are measuring 4.25mm, and my US5 is 3.75. I’m using the US5 based on my typical gauge for these patterns.

It also claims 60 rows fits 6/7, so I am assuming the 66 row pattern fits a women’s 9.5 shoe.

(The yarn label also states one ball is good for US size 1; Two strands of this are being held together. The yarn is 25% wool, 75% polyamide nylon.)