Lightsaber

A dual-phase lightsaber is a lightsaber variant that, at first glance appears to be identical to a standard lightsaber, with a small handle emitting an energy blade about 1.3 meters long. However, dual-phase light sabers include a complex array of multiple lightsaber crystals within the handle of the weapon, allowing the user to switch the blade’s length from the standard length out to a length of nearly 3 meters.

In its basic setting, a dual-phase lightsaber functions as a normal lightsaber. As a swift action, the wielder can switch to the extended blade setting. While on this setting, the lightsaber increases the wielder’s reach by 1 square, but the wielder also takes a -2 penalty to Reflex Defense against attacks made by adjacent targets.

A dual-phase lightsaber requires an energy cell to operate.

Source: Jedi Academy Training Manual, pp. 51-52