Minolta Color Meter III F (Color temperature Meter)

The Minolta Color Meter IIIF is a professional color compensation meter for ambient and flash with correction value memory. 
This makes it easier for photographers to maintain consistent color under various types of illumination.

The meter measures the color of the light illuminating the subject and determines the filtration required to correct that illumination for the film in use. When measuring both ambient light and flash, selecting the Color Meter IIIF's analyze function will subtract the ambient light and display only the measured results for flash light.

It provides filtration readings for two types of filters: LB (Light Balancing) and CC (Color Correction)

Measurements Can Be Taken for Any of the Three Major Film Types
Daylight (balanced to 5500k)
Type-A Tungsten (balanced to 3400k)
Type-B Tungsten (balanced to 3200k)

The Manual for this light meter is available here.

Uses 2 AA batteries.