#ED010411 Clip-On Alloy Motor Heatsink (Type 1)
#ED010421 Clip-On Alloy Motor Heatsink (Type 2)
#ED010431 Clip-On Alloy Heatsink w/Fan Mounting
Keep cool with these precision CNC machined Clip-On Alloy Motor Heatsinks! Available in a variety of designs so you can choose the exact method of cooling that best suits your needs, these heatsinks will work equally great for brushed and brushless motors.
Made from high-quality aluminium alloy for the best combination of heat dissipation and strength, you can choose from a solid design, a vented design to allow hot air to escape from motor can holes, or a design with a built-in 25mm fan mount for a constant blast of cool air. This heatsink features a ‘solid’ design to allow maximum contact area with the motor can, allowing heat to transfer from the motor to the cooling fins, where passing air can take away any heat from the motor.
Source : EDIT