A device and system for sterilizing objects, commonly dental, medical, or veterinary instruments, having a double door configuration that can provide entry of contaminated instruments into a sterilizer from a contaminated area and subsequently, post-sterilization, their pass-through directly into a sterile area through an exit door from said sterilizer. More specifically, the invention is a countertop, high velocity, dry heat sterilization device that is readily adaptable for those clinical areas requiring separation of contaminated and sterile areas for the processing of medical, dental, or veterinary instruments. The sterilization device utilizes a dual airflow pathway and a controlled heat delivery system to deliver to the sterilization chamber the supply air having temperature uniformity and air velocity required of the high velocity dry heat sterilization process.