This product was discontinued by Lesiter:
105.493 was a wide slot nozzle, straight jaw 120° bent at right angle that was made for the Triac ST, Triac AT and Diode PID/S. As the picture illustrates, it had its air outlet at it's tip of the angle bend.
The substitute 105.500 is the same basdic style, with a 90-degree bend instead of a 120-degree bend, and it has two air outlets, one on each side of the bent section (instead of a single outlet at the end/tip). The new style is better for overlap welding as it applies heat parallel to the seam that is being welded.