DOOMO Meter D Hot Shoe Light Meter
 
The Doomo Meter is a small, light accessory meter that serves well for people who use older Leicas, similar rangefinders, SLR or TLR cameras.

The meter conveniently slips into the camera's shoe (adjustable palcement of shoe bracket) while readings are taken.  

Three dials - one for ISO, one for aperture and one for shutter speed allow settings to be made.
A series of LEDs illuminate to tell the user when correct measurement has been achieved
 
Specifications:
Material: aluminum alloy
Color: black or silver
Battery: CR1632 x 1 (not included)
Battery Life: 60hrs (non-stop use), 60 days (regular use)