This high-torque brushless motor is built for larger mid-size drone platforms that need serious thrust and efficiency. With a 42.5mm diameter and longer 46mm body, the BL-4220D (3520 series) provides extra torque while maintaining a clean, professional look with its blue and silver anodized finish.

Key Specifications:

• Model: 3520 (BL-4220D)
• KV Rating: 900KV – Optimized for high torque and smooth power delivery
• Motor Dimensions: 42.5mm diameter × 46mm length
• Shaft Diameter: 5mm – Secure fit for larger prop adapters
• Recommended Propellers: 12-14 inch
• Voltage Range: 4S – 6S LiPo
• Drone Frame Compatibility: 500mm to 600mm frames

Why This Motor is a Great Choice for Drones

The BL-4220D 900KV excels on 500-600mm frames where extra power and payload capacity are required. Its lower KV rating delivers strong torque with 12-14 inch props, making it ideal for carrying heavier cameras, gimbals, or extended flight batteries while keeping current draw manageable.

• High Torque Performance: Excellent for stable hovering, heavy-lift applications, and responsive control even under load.
• Efficient Power Delivery: Runs cool on 4S-6S setups, supporting longer flight times compared to higher KV motors on the same frame size.
• Robust & Reliable: Reinforced construction and quality bearings handle demanding flights and occasional hard impacts.
• Smooth & Quiet Operation: Low vibration design helps maintain clear video footage and reduces wear on the airframe.

Perfect for cinematic drones, heavy-lift photography rigs, long-range FPV cruisers, or any 500-600mm build that needs reliable lifting power without sacrificing efficiency.

Ready to upgrade your drone? The BL-4220D gives you the muscle you need for bigger props and bigger missions while staying efficient and dependable in the air.

Models    3520(BL-4220D)
KV    900
Motor diameter (mm)    42.5
Motor length (mm)    46
Drone frame sizes (mm)    500-600
Propeller size (inch)    12-14
Voltage    4S–6S LiPo
Shaft diameter    5mm