They work just like in the cartoons and are really easy to make first what you willl need is:
2 Metal cans (any size works)
Several feet of wire (depending on how long you want the distance apart)
Something to drill holes with ( I just used a hammer and nail but you could use other tools)

Step 1: Drill a Hole

You first have to start by drilling a small hole on the center of the bottom of the can (make sure top part of can is open)

Step 2: Wire

The Next step is pretty easy just get your wire at the length you chose then insert each end through the hole you just made then tie in a knot so it cant get out.

Step 3: USE

Now to use it just have one person on each end and talk through you should here the persons voice on the opposite side (Make sure you have the wire tight while talking) this happens because sound is transmitted through vibrations while you talk through it the vibrations echo into the can through the wire and to the other can.
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