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German twisted CO 63 stitches to accommodate a 2x1 rib.
20 rounds 2x1 rib, then inc 1 stitch to get to 64.
34 rounds plain st st for leg, then begin heel flap on second half of round with CC (grey).
knit heel flap until 17 sts in each slipped stitch column, turn heel.
Pick up 18 sts along each side of heel flap with MC.
Gusset decreases every other row.
BOR is at beginning of instep stitches
47 rounds for foot (one round of grey before beginning toe decreases)

40g remaining of CC
52g remaining of MC