I CAME ACROSS 4 hp 48'S, 3 ARE THE 48gx, AND ONE IS THE hp 48sx. 2 of them are still in the box, never been used! As a onetime user of these, I know that they can be treasured by some surveyors. There are also two 48G's, still in their box. An old eccentric retired NASA engineer had collected these, and his estate was auctioned off, and I got these, among other items. If anyone is interested, I am offering them for sale. Make an offer; I have no idea what they are worth. Send an email, and I can send pictures. [email protected]. This site says the pics are over the limit (7mb)