Announced this week on the Align Taiwan site is the latest 450 size brushless motor. This motor is a true outrunner design similar to Scorpion where the outer can spins. The BL450M is designed as a “shelterless” outrunner which means it doesn’t have an outer can protecting the spinning part of the motor. The Align BL430SP that comes with the T-Rex 450 Pro is actually a “sheltered” design and thus has had issues with head build-up during flight. The BL450M is 3500kv while the BL430SP is 3700kv.