The Megajolt ECU includes an ignition retard rev limiter as standard. Megajolt/E MK2 (the one with USB socket on it) also includes a hard cut limiter in the case.
For earlier ECUs this hard cut module fits inside the case and works with the existing soft rev-limiter. When installed the soft-limit of the ECU automatically retards ignition timing to zero degrees 100 RPM before the hard limit activation point. This makes for a progressive application as you reach the rev limit.