The DS821 servo is a powerful, accurate sport digital servo recommended for RC airplane applications up to 1.20-size. For helicopters, the DS821 operates best with 30-size glow models, and up to 50-size electric. Loads and vibration in larger models may cause premature failure of the servo resulting in damage or injury to property and persons.

Important: Do not use liquid thread lock with the DS821 servo!

Do not use any form of liquid thread lock to secure the servo arm screw to the output shaft of the DS821 servo. Chemicals in these liquids react with the polycarbonate gear set causing the plastic to become brittle, fracturing the final output gear.

Type: Digital Hi-Torque
Torque: 72 oz/in @ 4.8v, 88 oz/in @6v
Speed: .19 sec/60 @ 4.8v, .15 sec/60 @ 6v
Dimensions (WxLxH): 0.74"x1.50"x1.47"
Weight: 1.5 oz
Bearing: Single Ball Bearing
Motor Type: 3-pole ferrite
Gears: Composite
Application: Standard size-digital servo upgrade for sport pilots

Thread Locker is not needed or recommended for use on the servo output horn screw. As with many plastics, thread locker can damage and weaken the output gear potentially causing a failure. No thread locker is necessary on the output horn screw.

If you have any further questions, please contact our product support team for further assistance. You can call us at our toll free number at 877-504-0233 or email at productsupport@horizonhobby.com.