Disclosed is a preferred mold design for producing plastic, molded preforms, which may be blow-molded into a container of a final, desired shape. A preferred mold includes a temperature control system for maintaining the preform mold at a desired temperature. The temperature control system can pass fluid through channels within the preform mold to cool plastic that is injected into the preform mold. In some arrangements, a mold comprises a neck finish mold, the neck finish mold comprising high heat transfer material positioned to transfer heat away from melt within a mold cavity of the mold.