You will need 2 DP needles size US 3/3.25 mm needles for I-cord.
You will also need 6 buttons. Rowan used #RW5030 from Bedecked in the UK.

Finished measurements:
Back width: 18.75(20.25, 22.75, 24.75, 26.5, 28.75)“ 47.5(53, 57.5, 63, 57.5, 73) cm
Finished length to shoulders: 26(26.75, 27.5, 28.25, 29.25, 30)” 66(68, 70, 72, 74, 76) cm
Sleeve to underarm: 18.5(19.25, 20, 20.5, 20.75, 20.75)“ 47(49, 51, 52, 53, 53) cm

Yarn used:
Rowan Denim Revive
A. Silt 216 - 9(10, 11, 12, 131, 14) balls
B. Cream 210 - 7(7, 8, 9, 9, 10) balls