Identify use & manufacturer of a tool or device. 2 aluminum tubes app.
48" long and 1.5" in diameter,which couple together to form one long
rod. Each has a black oval-shaped "optical" device on one end with a
white translucent plastic insert, a "bullseye", and a number 175418.
There is a molded channel that runs the length of each tube that is
about 1/4" in diameter. Each tube feels as though it has something
inside it, i.e. not hollow, as they are relatively heavy. No
electrical connections of any sort. Has a canvas and leather carrying
case. Possibly German in origin. First reaction on seeing it is that
it is a surveyors tool.