Maker: Weston Electrical Instrument
Model: Model 617 Type 2
Original Price: $12.50
Cell type: Selenium
Measure type: 2D Incident
The Weston 617 Type 1 was a big old thing—it had two big selenium cells and a meter in the middle; it was about the width of a set of binoculars and nearly as heavy.
They almost immediately released this unit, which is a little less than half the size, and it only has one cell. But even though it's still heavy, it's easily held in one hand (sideways, and shown in the advertisement), and it's got that great Weston calculator dial.
In a couple years, they would be able to further lighten it and slim it down to become the 650 Senior. That's how fast the state of the art was moving at the time.