E-Z Nurser prevents "gulping" and helps lambs gain weight faster right from the start. The bottle fashioned of a special plastic with pint markings won't crack or break and lasts indefinitely. It's light and easy to clean and sterilize. Lamb Nipple is rubber with cross-cut opening and air hole which prevents vacuum and promotes flow. Complete Nurser includes 2-quart bottle screw-on cap and lamb nipple. Replacement caps and bottles may be seen in the Calf Nursing Bottles section. Wt. 12 oz.