It gives more exposure of the vaginal walls than Cusco's Speculum and therefore is preferred for gynaecological surgeries. it is possible to slide the instrument around the vaginal wall to enable better visualization. The groove in the middle of Sims' speculum allows free flow of secretions and blood to the outside, thereby keeping the area dry. Sims' speculum is available in various sizes, and the size appropriate to the vaginal dimensions of the woman is chosen for use.