Thanks to Soldier Systems Daily for this sneak peak.

One aspect that I liked of the older and bigger Millenium Weaponlights is the XM dual switch tailcap. It has a rear mounted tailcap switch that clicks on and off or can be used momentarily. The XM also has a receptacle to receive the pigtail remote tape switch. That was not the case with the Scoutlights. If you wanted to use the tape switch, you had to use the UE tailcap. However if something happened to the tape switch, you could not turn the light on, unless you used the regular tailcap

Well now SureFire is making a new dual switch tailcap for the E-series/Scoutlight lights.