An insert for a mold comprising a plug, having an insert face, and a receiver defined by a sidewall with one of the plug and the receiver having a groove that receives a guide that extends from the other of the plug and the receiver so as to facilitate rotation of the plug while opposing withdrawal of...http://www.google.fr/patents/US6308929?utm_source=gb-gplus-shareBrevet US6308929 - Mold insert
