This is Charlotte. She models some of our size S jumpers. Her measurements are:

Height: 5ft 7"; Bust 35"; Waist 30"; Arm length 24"
Size UK/US Bust
Extra Small UK 6 / US 2 up to 32"
Small UK 8-10 / US 4-6 34"-36"
Medium UK 12-14 / US 8-10 38"-40"
Large UK 16-18 / US 12-14 42"-44"
Extra Large UK 20+ / US 18+ 44"+