Vesper created this lightsaber several years after joining the Jedi Order. The blade is purple in color. It is a dual-phase design that can be changed with the press of a button, lengthening the blade almost instantly from a standard 1-meter out to 2-meters. There are also buttons to quickly change them from lethal to stun setting.
Legal wherever lightsabers are legal.
This is just a write-up to describe Vesper's lightsaber.