Hobbywing X9 power system combo with an light-weight structure design integrates motor, ESC and 34" propeller with 40mm tube, it is great for  heavy payload drone with 40mm arms. The max. thrust for singe axis can reach to 21.5kg, recommended take off weight for each axis is 7kg to 9.5kg.
Specifications: 
Item Brand: Hobbywing
Product Name: XRotor 9 Power System Combo
Max. Thrust: 21.5kg/Axis (46V, Sea Level )
Recommended Takeoff Weight:7-9.5kg/Axis (46V, Sea Level )
Recommended LiPo Battery: 12S（LiPo）
Operating Temperature: -20-55℃
Combo Weight: 1450g
Waterproof Rating: IPX7

Motor
Stator size: 96x16mm
KV Rating: 110
Internal resistance: 0.031ΩBE
Maximum current: 100A
Motor outer diameter: Φ103.5mm
Paddle clamp installation size: Φ25mm-4xM3; Φ31mm-4xM3
Bearing: imported ball bearing (waterproof)
Applicable carbon tube outer diameter: 40mm

ESC
Model: X-rotor/120A-FOC
Battery: 12-14S lipo
PWM input signal level: 3.3V/5V
Working pulse width: 1100μs-1940μs (curing, calibration is not supported)
Maximum allowable voltage: 52.2V
Maximum allowable current (continuous): 120A
Maximum allowable peak current (3 seconds): 150A
BEC: none

Propeller
Diameter×Pitch: 34x11 inch