Get ready for some real power on a tiny scale.
These 803 brushless motors are very, very fast, meant to push the limits of power on the 65mm frame size. To my knowledge there has never been a 803 motor that is as fast as 20,000kv.
First of all, why use such a fast brushless motor for 65mm builds? The answer is transient response. These motors prouduce about the exact same amount of thrust as the much lighter 802 22,000kv Double Deuce Juice motors, but they get up to speed much faster. They let you move all that air much more quickly than 802 motors. But they're also harder on batteries! These motors have to be used with a timer, and depending on the setup you may get as little as 90 seconds of flight time, tho with a 333mah HV battery you might expect two full minutes of intense flight. These motors are NOT for everyone, but if you're looking to max out pure raw power on this scale, this is the motor for you.
These 803 size motors also use a real bearing, not a bushing. This adds a little weight, but makes up for it in power. The bearing also adds to the lifetime of the motor.