You will need a 6” (15 cm) zipper for the neck.
Note: the pattern reads 15 cm (4”) but that is not correct.

Finished measurements:
Chest Circumference: 24.5(26.5, 28.5, 51.5)“ 62(67.5, 72.5, 80) cm
Finished length: 17(18.5, 20, 21.75)” 43(47, 51, 55) cm
Sleeve to underarm:9.5(11, 12.5, 14.25)“ 24(28, 32, 36) cm

Yarn used:
Rowan Baby Merino Silk DK
A. 684 Bluebird - 5(6, 7, 8) balls
B. 692 Leaf