Price (new): $69.95
Designer: Thos. Blakeslee and Erwin Bryll
US Patent: 3,709,615
Battery: two PX23
Cell Type: Silicon blue
Measure type: Flash (both 3D incident and reflected)
Modern Photography Review: July 1969
This is an early flash meter, and one of the better ones; the bad part is that it requires a cable to sync the flash. You set the film speed (the big silver ring), hook the cable to the flash, put the meter where your subject is and point the incident dome at the camera lens, then push the red button on the side of the meter to pop the flash. The meter needle will swing point to the ƒ/stop to use. If it goes off the scale (the blue area), you use the slide-switch on the side (it's not visible in this photo) to rotate the scale.
A big meter—about the size and shape of an oven timer. The controls are big and easy to use; but it looks to me like it was designed to be used in the snow with gloves; yet it's really meant for studio work.