Stacked camera sensors have been a thing for a while now; they have improved sensitivity to light by stacking translucent photodiodes on top of each other.
The Nichia 719A is the inverse; translucent LEDs are stacked on top of each other (in a single package) for increased intensity.
This might be my first zebra. Been wanting to get one just for practical use (efficiency and durability).
You wont be disappointed.