It is a speaker, so it plays audio. It is basically half of an aux cord connected by wire to a paperclip which sends an electrical signal to a set of magnets. which convert the electromagnetic signal to sound waves through a plastic film.
Steps
Step 3 Wrap the magnets and the paper in magnet coil. Make sure to leave both ends of the wire showing and shave off the outer layer of the wire.
Step 4 Carefully remove The first layer of paper under the magnet coil. Step 5 Glue down the magnet coil so it can't move. Step 6 take a plastic cup and cut a hole in the bottom the same size as the magnets. Step 7 Attach a piece of tape from inside the cup to cover the hole Step 8 Attach the magnet to the outside bottom of the cup. I f done correct it should look like this
Step 8 Take a paper clip then twist the top until it turns into a small spiral Step 9 Attach the paper clip to the side of the cup so the spiral is above the magnets Step 10 Take a pair of head phones and cut of the end with more than 2 inches of wire left.
Step 11 Take the AUX cord and attach the yellow and black wires to the ends of the copper wire with electrical tape.