Gorg GOTS organic cotton cardi with tie belt detail.
This is more an oatmeal shade than sand as it is fairly cool in tone. The sleeves are quite wide but can be turned up and seem to stay well in position.
Sizing - small - 10-12, medium - 12-14, large 14-16 but there's a little leeway due to the style of this cardigan. It may be fine for a size 18.