Concealment: Unconcealable
This is a large metal parabola, usually made of thin brass plates or or waxed paper. It works by concentrating sound from a certain direction, and allows you to hear as though you were one-tenth of the actual distance from whatever you are listening to. It also blanks out sounds originating more than ten meters from your target point. In this way, shouted orders can be heart at five hundred meters, a normal discussion can be heard up to a hundred meters away and whispers up to fifty meters away. Halve these ranges under noisy conditions, and halve them again if there is a breeze.
When not in use, it is folded down to resemble an oversize fan about a meter in length.