Sullivan S753 - Skywrite Smoke pumpElectronically controlled Smoke Pump for onboard smoke systems. Using the same ultrasonically sealed direct drive pump head as our other electric pumps, this lightweight onboard unit has a miniature microprocessor controlled electronic pulse drive speed control. You can set smoke rate with your transmitter trim, and mix the smoke with the throttle channel if desired. Works with 6V to 12V battery packs. Note: For best results battery of 9. 6V or less