Here's a bundle offer: buy a phone, get free calls forever! Of course, this only works if you have a friend with a similar phone and some cable. This phone is an excellent addition to the OP of your neighborhood watch or a means to discuss things in private - it's fairly difficult for Facebook or Google to monitor your calls on these things!

Field phones like this are old-school analog telephone technology and this East-German example is a rather appealing combination of bakelite, rubber, and metal. If you're really fanatic, you'll get a switchboard and build a private network of your own! Two phones should work up to a distance of 100 meters with just a parallel cable, you need signal amplifiers for greater distances.

The lid has a cheat sheet for the phonetic alphabet and it's not the NATO/aviation standard you may be familiar with. Memorizing these will make you a popular participant in Wheel of Fortune. Once you've used the letters F for FRIEDRICH, S for SIEGFRIED, and K for KONRAD, the others will offer to buy your vowels to shut you up and you can head for the bar.

The battery compartment is too large for the five AA batteries the phone runs on and is difficult to open. But it's waterproof which is a bonus. First, you loosen two screws with rectangular rings on them - this allows the rubber seal to let go of the sidewalls. Then, you pull out the battery tray and open it with a flat-head screwdriver (patented by the Devil himself, by the way). Finally, you get to install the batteries and reverse the whole process. If an officer tried to reach you meanwhile, too bad for you. In some cases, the battery tray may be missing. It's nothing some signals ingenuinity couldn't handle but you have been warned.

Genuine East-German surplus

The phones are in very good condition but more than half a century old, so expect some wear. They all should work, but we do not have the resources to test them. Some scratches, general wear, and old markings may be found.