NAMCO NINJA ASSAULT SD Mode D'emploi page 59

Button screw
(M4 x 25)
Button screw (M4 x 10)
Cap screw (M3 x 10)
facing the back of the gun).
Gun casing (R)
Button screws (M4 x 10)
Ensure that the flat face of the lens is
Note direction of lens
(Convex surface faces the muzzle.)
Hexagon cap nuts (M4)
Gun casing (L)
Lens