3900KV Brushless Motor & Marine ESC Combo. This is a great combo for converting RC boats with 500-600 size motors from brushed into brushless! You can use either LI-PO or Ni-MH batteries up to 13v. 3900KV Motor Details 3650 3900kV 500-600 Size Brushless Motor Upgrade Ideal For Model Boats and Cars! This motor is a fantastic upgrade from brushed to brushless for very fast speeds! Replace your 500-600 size brushed motor with this. VERY SPECIAL OFFER FOR THIS RANGE OF MOTORS!! ONLY £19.99! Key Features 4-pole design for high torque and fast response CNC machined, high-strength aluminium housing for optimum heat dissipation Motor winding made of pure, double insulated copper wire Precision ball bearing for optimal running smoothness and extended service life Highly flexible silicone connection cable with soldered 4mm plugs High strength and polished steel 3.17mm rotor shaft 3.175mm/5mm Shaft Diameter 3650-3900kv Specifications: Watts: 900W Max voltage: ≤13V Max Amps: 69A Rotor Poles: 4 KV(RPM/Volt): 3900KV Max RPM: 50000 Diameter: 36mm Length: 50mm Shaft length: 15mm Length of Extend Shaft: 15mm Outer Shaft diameter: 3.175mm Plug type: 4mm golden banana plug Cable Length: 290mm 80A Marine ESC Details: A quality, waterproof, marine speed controller sporting ZTW’s assured, ultra-reliable software Product Description Designed specifically to provide a solid hassle-free performance, Shark programmable brushless marine ESCs offer high quality components programmed with ZTW’s mature software at a price that’ll have you reaching for your bank card. Water cooled, waterproof and packing a built-in switch-mode BEC – Each speed controller features Over Temperature Protection and includes a high-throttle safety function that prevents the ESC from arming the motor if the throttle stick is not fully closed. Fact is, for those who seek an affordable fit ‘n’ forget solution, there really isn’t a better alternative. Key Features Light and compact. Over-heat protection circuitry. Low voltage protection Lost signal protection Super smooth linear throttle response Waterproof Water cooling system Forward and reverse with adjustable endpoints Suits 5 – 18 cell NiMH packs ESC Technical Specifications Weights & Dimensions Weight 118.5g 4.18oz Shipping Weight 0.14kg 0.31lbs Product Height 14mm 0.55in Product Width 37mm 1.46in Product Length 68mm 2.68in