This is the Obi-wan Kenobi A New Hope Limited Edition lightsaber. Master Replicas built this replica from source materials in the LucasFilm archives, but the original prop has since been lost, I believe. The original prop was frankensteined together from a european sink knob for a pommel, a graflex flash gun attachment band with calculator LED's on the control box, a WWI British rifle grenade for the body section, and a Rolls-Royce jet engine balance pipe for the emitter. The first of what would come to be known as the "thin-neck sabers", Obi-wan's lightsaber from A New Hope is one of the most sought-after pieces for collectors. Limited Edition 1356/2500.
More from Star Wars: Episode IV - A New Hope (1977)
