there are 2 size for the vest and you can regulate the bust size to a lesser extent

bust size is 100/120cm for size 1/2

Yarn: Use 2 strands of yarn together
Fingering weight yarn (merinowool 100% 100g 400m)
Mohair (kidmohair 76% silk 24% 20g 200m)

Yarn Usage
size 1
fingering weight yarn 270g/990m(3skeins),
mohair 99g/990m (5 balls)
size 1-1
fingering weight yarn 300g/1200m(3skeins),
mohair 120g/1200m (6 balls)
size 2
fingering weight yarn 350g/1400m(4skeins),
mohair 140g/1400m (7 balls)
size 2-2
fingering weight yarn 390g/1560m(4skeins),
mohair 156g/1560m (8 balls)

Can vary by your desired length and your tension

Needle: body 4.0mm circular needle
Rib 3.5mm circular needle
Neck: 3.5mm, 3.75mm circular needle
Gauge:
1010cm 4.0mm needle 22st 48 row
using the pattern ‘diamond honeycomb’