Not really sure how it works.

This vintage Weston Photronic Light Exposure Meter, Model 650 is a must-have for any photography enthusiast. Its compact and durable design allows for easy portability, making it a great addition to any photography kit. With its universal exposure meter feature, it can be used with a variety of cameras and tripods.

The leather case adds an extra layer of protection to the meter, ensuring it stays in good condition for years to come. This classic piece of equipment is perfect for both novice and professional photographers alike.