Yeah it's got more to do with whether there is a trigger or not.
The most common trigger-less systems that all swap boxes are
Tomos a35 (static/RL)
Kinetic (static no RL)
Parmakit (retarding no RL)
Ktm cobra cdi from China (static no RL)
80cc motorized bicycle CDI from China (advances and prone to failure)
There is also the puch ducati and a derbi (ducati, motoplat? ) That are similar but not common in USA