13: LED Bar Graph

I bought 3 of these from All Electronics (as I recall). $.50 each.

I assumed these were a 1-piece item, but nope:

note the +/– markings

Each separated LED is dimly marked too:

Too bad they didn't build the ground-side resistors in. Otherwise, the 2 pins neatly fit in adjacent breadboard rows -- and make for tidy wiring.