ZTW Spider Series ESCs are high quality speed controllers designed specifically for multi-rotor aircraft. Flashed with popular SimonK firmware for multi-rotor. Spider Series ESCs feature up to 600Hz refresh rates for an incredibly smooth yet crisp flight controller response. These ESCs also feature excellent throttle linearity without sacrificing a rapid, crisp response to throttle input. As usual. Spider Series ESCs come standard with the ZTW quality, performance, and reliability you have come to trust.