A mold interlocking device that includes a first portion attached to a mold half that has a head with a channel and an insert therein that is received in a pocket of a receptacle of a second portion that is attached to another mold half. In one embodiment, the head comprises sidewalls each with channels that receive a replaceable insert therein. Preferred inserts include rollers, plates, plates with lubricating plugs, and plates comprised of layers. In one embodiment, each sidewall of the head has a tapered section disposed between a mounting base and a straight section and each pocket is defined by a complementarily contoured sidewall. In another embodiment, each head sidewall further includes a second tapered section adjacent the free end of the head.