Driza Bone Size 1: 3XS / 81cm chest / XXXS. Driza Bone Size 2: 2XS / XXS. Driza Bone Size 3: XS / 95cm chest. Driza Bone Size 4: S / 100cm chest. Driza Bone Size 5: M / 105cm chest. Driza Bone Size 6: L / 110cm chest.