The KST X20-3012 HV Brushless Digital Metal Gear Servo is a standard-size HV brushless servo for RC cars, aerobatic airplanes, and jets. KST public documentation verifies the 35KG configuration with high torque and fast response in a 40.5 x 20 x 38mm case.
Verified KST data for the 35KG configuration lists a DC 6.0V-8.4V voltage range, up to 35Kgf.cm torque at 8.4V, and 0.11sec/60deg speed at 8.4V. The servo uses a brushless DC motor, hardened steel gears, potentiometer feedback, and 2 ball bearings.
The current OpenELAB Shopify product contains 35KG and 40KG variants. Because public KST documentation available for this listing verifies the 35KG version, confirm the selected variant before using the data in a torque-critical build.
Product Images
Features
- 35Kgf.cm verified torque - Public KST documentation verifies 35Kgf.cm at 8.4V for the 35KG configuration.
- 0.11sec HV response - Listed speed reaches 0.11sec/60deg at 8.4V.
- Brushless DC motor - Supports high-output control in cars and aircraft.
- HV operating range - Supports DC 6.0V-8.4V.
- Hardened steel gears - Adds durability for high-load control systems.
- Aluminum alloy case - Provides a rigid standard servo housing.
- 25T 6mm output spline - Uses the listed output spline.
- 2BB construction - Uses dual ball bearings for output support.
- 100deg default travel - Default travel is listed as +/-50deg.
- Two Shopify variants - OpenELAB currently lists 35KG and 40KG style options.
Specifications
| Parameter | Value |
|---|---|
| Model | KST X20-3012 |
| Verified Configuration | 35KG |
| Shopify SKUs | KST-X20-301235; KST-X20-301240 |
| Rated Voltage | DC 7.4V |
| Voltage Range | DC 6.0V-8.4V |
| Torque | 25Kgf.cm @ 6.0V; 30Kgf.cm @ 7.4V; 35Kgf.cm @ 8.4V |
| Speed | 0.15sec/60deg @ 6.0V; 0.12sec/60deg @ 7.4V; 0.11sec/60deg @ 8.4V |
| Working Frequency | 1520us / 333Hz |
| Default Travel Angle | +/-50deg = 100deg total |
| Command Interface | PWM command; pulse length 900us-2100us |
| Output Shaft Spline | 25T, 6mm |
| Case Material | Aluminum alloy |
| Motor Type | Brushless DC motor |
| Gear Set Material | Hardened steel |
| Position Sensor | Potentiometer |
| Ball Bearing | 2BB |
| Case Dimensions | 40.5 x 20 x 38mm +/-0.2mm |
| Weight | 72g +/-10% |
| Temperature Range | -10C to +65C |
Variant Options
| Variant | Confirmed Details |
|---|---|
| 35KG / SKU KST-X20-301235 | Public KST technical specification verifies the 35KG performance data shown above. |
| 40KG / SKU KST-X20-301240 | Shopify variant exists, but matching public KST technical specification was not confirmed; verify selected configuration before torque-critical use. |
Reference Documents
Application
- Large RC aircraft - Suitable where a standard-size HV servo and high torque match the airframe requirements.
- RC cars and crawlers - Can be used in compatible steering systems after checking size, spline, and voltage.
- Aerobatic airplanes and jets - Works for demanding control surfaces when torque and speed match the design.
- Scale model control - Useful for high-load PWM servo actuation in compatible scale models.
- Servo upgrade projects - Can replace compatible standard servos after checking case size, output spline, and travel.
- PWM-controlled mechanisms - Supports custom mechanisms using the listed PWM command range.
Packing List
| Description | Quantity |
|---|---|
| KST X20-3012 HV brushless servo | 1 |
| Accessory pack | 1 |
FAQ
OpenELAB currently lists 35KG with SKU KST-X20-301235 and 40KG with SKU KST-X20-301240.
A matching public KST technical specification for the 40KG variant was not confirmed during this update, so only the variant name and SKU are listed.
For the verified 35KG configuration, the technical specification lists 35Kgf.cm at 8.4V.
For the verified 35KG configuration, the fastest listed speed is 0.11sec/60deg at 8.4V.
The verified KST specification lists DC 6.0V-8.4V.
The package listing confirms one X20-3012 HV brushless servo and one accessory pack.
The technical specification lists a 25T, 6mm output shaft spline.
Confirm the selected 35KG or 40KG variant, 40.5 x 20 x 38mm case, 25T 6mm spline, voltage range, and load requirements.