Also available - Extra powerful magnet version which produces more torque. This is just the core motor, and you will need to re-use your own existing worm gears or flywheels. These can be removed from your old motor with a bit of heat.
5 Pole Core Motor For Hornby King Class - X7011
Hornby OO Gauge X4026 Various Locomotives 5-Pole Can Motor/Power Unit/Brass Worm
Romford Bulldog 4mm OO Gauge 5-Pole Loco Motor - Kit or Hornby X04 Replacement