thinkbaby Set of Two Medium Flow Nipples - thinkbaby's Cross Cut (Medium Flow) Nipple has been specifically designed to reduce the incidence of colic (gas and spit up).  Stage II (Medium flow) Nipple  Patented Anti-Colic device built into nipple Made from Silicone Packaged in recycled materials Two nipples per package Cross cut design helps reduce the chance of spillage during use