The optional Instant-Setback Cubby is a unique Tip & Tool Stand for use with PACE IntelliHeat units including Models ST 30, ST 50, ST 65, ST 70, ST 75, ST 115, WJS 100, MBT 301 & MBT 350. When connected, it automatically puts the system into Setback Mode when the TD-100 Iron has been in the cubby for 45 seconds. Setback Mode means that the temperature is reduced to just below solder melt temperature (176°C/350°F) so the corrosive action of the leaded or Lead-Free solder is stopped, maximizing the life of your tips! The system returns to normal operation within seconds when the iron is removed from the cubby.