graduated in centimeters & inches, 13-1/2″ (34.0 cm) Martin Pelvimeter is used in obstetrics and gynecology to assess the size of the female pelvis in relation to childbirth to determine whether natural vaginal delivery is possible. The pelvimeter features two bulbed arms to grasp the pelvis width and a ruler at the hinge graduated in centimeters and inches. Please note that website images are often representative of the product family and may not conform to the exact specifications or features of the item you select. The final specifications will match the description of the specific catalog item you select.