Novak Ballistic 540 Vented end bells
Novak’s new Ballistic 540 Vented end bells & bearing racing upgrade kit includes everything needed for this performance update. Both the rear and front end bells have machined cooling vents which allows excess heat to escape, resulting in cooler temperatures and higher motor performance. Additionally, the front end bell has a precisely installed ball bearing. This upgrade kit is compatible with all Novak Ballistic 540 Brushless motors.
Source: Novak [teamnovak.com]