The TransTemp transparent tube furnace was originally developed at the Lincoln Laboratory on the campus of MIT. Unlike conventional furnaces, the TransTemp becomes transparent at approximately 600°C, which makes it possible to see a process as it takes place inside the furnace. TransTemp transparent furnaces use a gold mirror that reflects infrared radation and acts as an insulator. The use of only a gold mirror for insulation minimizes mass and allows for very fast heat up and cool down rates. The maximum recommended operating temperature of the TransTemp tube furnace is 1000°C.