Further testing revealed significant problems, however. To reach break-even, the system would have to meet several goals at the same time, a combination of temperature, density and the length of time the fuel is confined. In April 1986, TFTR experiments demonstrated the last two of these requirements when it produced a fusion triple product of 1.5 x Kelvin seconds per cubic centimeter, which is close to the goal for a practical reactor and five to seven times what is needed for breakeven. However, this occurred at a temperature that was far below what would be required. In July 1986, TFTR achieved a plasma temperature of 200 million kelvin (200 MK), at that time the highest ever reached in a laboratory. The temperature is 10 times greater than the center of the sun, and more than enough for breakeven. Unfortunately, to reach these temperatures the triple product had been greatly reduced to , two or three times too small for break-even.