A number of TFT solutions are offered. Serial TFT, I2C TFT, USB TFT, RS422 TFT, SPI TFT and Parallel 24bit RGB TFT. TFT, or Thin Film Transmissive, display technology uses the same control techniques as an LCD, but permits larger screen sizes by adding transistors to address pixels by row and column rather than individually. Additionally, TFT units offer red, green, and blue elements for each pixel to produce a full range of colour output. The brightness of each colour element is individually controlled by a number of bits, typically between 5 and 8, to produce up to 16 million colours. These units are driven by an LED backlight which requires moderate power input, and can be varied to control brightness, typically up to 600 nits. These units have an operating range similar to LCDs of -20C to 70C, but offer increased contrast performance, typically up to 500:1, and viewing angles of up to 140 degrees. High display resolution and touch overlay options make this technology attractive to higher end HMI applications. TFT is available on GTT, EVE2, HTT and Parallel Displays.