This is a hard to find remote controller for what seems to be a Helium Leak Detector, DuPont.  I cant find lots of info on this unit.  The part number for unit does not show up anywhere, only the 24-120B.  PLease ensure this fits your application before buying.  

There is a place in the back for phone jack.  There is alot of empty space in the box, but all the items attached to the panel are on in place.