A postcard or post card is a rectangular piece of thick paper or thin cardboard intended for writing and mailing without an envelope. There are novelty exceptions, such as wood postcards, made of thin wood, and copper postcards sold in the Copper Country of the U.S. state of Michigan, and coconut "postcards" from tropical islands.
In some places, it is possible to send them for a lower fee than for a letter. Stamp collectors distinguish between postcards (which require a stamp) and postal cards (which have the postage pre-printed on them). While a postcard is usually printed by a private company, individual or organization, a postal card is issued by the relevant postal authority.
Does anyone see anything slightly strange about the camo colors of these units? Maybe I'm missing something, but I would think that regardless of their efficiency, their heat, electromagnetic, and sound properties would make them a larger target than if they just painted them orange.
Now, here's an appropriate use for hybrids and alternative sources.
At this year's MD&M West show, lots of material suppliers are talking about new formulations for wearables and things that stick to the skin, whether it's adhesives, wound dressings, skin patches and other drug delivery devices, or medical electronics.
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