Initially, enthusiasts used laboratory-grade thermal immersion circulators, often bought used on eBay, which required very careful cleaning and, even then, were not recommended for kitchen use.[by whom?] Beginning in 2008, Auber Instruments and Fresh Meals Solutions made available comparatively inexpensive yet highly accurate PID controllers with attached thermocouple probes that could be used to control commercial rice cookers, slow cookers, electric stock pots, and similar apparatuses. In late 2009, several machines intended for home use and less expensive than laboratory-standard equipment were available for purchase.[21]