Built-in adjustable heater control up to an element temperature of 450°C and magnetic stirring control up to approx. 520rpm with auto-reverse facility and automatic stirrer bar trap; the stirrer unit has an independent power supply. Polypropylene outer case is resilient and chemically-resistant. Even at full power output, the exterior remains ''cool-to-touch'' due to good heating element insulation. All heating mantles have support clamp for rods of up to 12mm diameter, and are double fused, with earth (ground) screen to protect the user from electric shocks. Available as 220-240 V 50/60 Hz models; spare heater cartridges are available on request.