Vintage Large Radio Crystal US Army Signal Corps "H" 5-pin Brown Bakelite Case

Description

Up for sale here is this radio crystal or something similar.  It's got a big "H" on the top and appears to have been made for the US Army Signal Corps once upon a time.  If you have any idea what this is, please let me know.  Please see my pictures for details.
US shipping and handling is , and international is , no matter what quantity you buy.  All my small parts are set up for combined shipping, so just use the "add to cart" feature and then check out all at once, and it will combine shipping.  I accept Paypal.  If you have any questions, please ask.
I have a number of other parts, collectibles, Magic cards, and vintage electronics listed--feel free to take a look!