Double or Dual Single Triggers for Dominator Pedals. Advanced laser technology is deployed to monitor motion and velocity. When the motion and velocity abruptly stop (the beater hitting the drum head or pad) on the forward stroke, a trigger signal is sent to the drum brain. - Accurate to 1.5 milliseconds - No false triggers or crosstalk Universal Power Supply is included. Only Fits Dominator Pedals. Pro1-V Item Numbers are P1VSB1-1 and P1VSB1-2.