The L-s4 laser cannon was a laser cannon manufactured by Sienar Fleet Systems. Two laser cannons of this model were utilized on the TIE Advanced x1 prototype starfighter.[1]
Behind the scenes
The L-s4 laser cannon is non-canonically pictured in the 2006 LEGO Star Wars Ultimate Collector's Series set 10175 Vader's TIE Advanced.[1] The use of L-s4 laser cannons for the TIE Advanced x1 in the set differs from the version in the official Legends continuity, which utilizes L-s9.3 laser cannons instead.[2]
Sources
LEGO Ultimate Collector's Series (Set: 10175 Vader's TIE Advanced) (First pictured)