Analog panel meters are arguably not as blingy or flashy as LEDs, but their simplicity adds a touch of elegance and makes them easier to read quickly.
This Small -15V to +15V Panel Meter is about handheld-size, with three screws to open up the panel and replace the backing paper, if you like. It's great for analog projects that have a split power supply or large voltage swings.
The back is constructed with two bolts the left coil is marked below with Negative to distinguish the positive from the negative. You can wrap a wire around the bolt and use the nuts to keep them in place, or use alligator clips.
Panel Dimensions: ~60mm x 55mm x 10mm