D840WP WV Mega Scale SpeedDescription Part of Hitec's D Series servo range, the steel gear D 840WP features industry leading high resolution, state of the art ultra response technology, a 32 bit MCU and a 12 bit ADC for unprecedented programmability and flexibility. The result is a significantly smoother movement and a 4. 8 8. 4 volt range, allowing use with any common battery chemistry without the need for adapters or regulators. Featuring Hitec's 15 tooth HD output spline