Easily fits in your hand to be thumb-operated. The register advances by one digit, up to 999, each time the button is pressed. A turn of the side knob resets the register back to zero. It's a great tool for counting algae cells, zooplankton, fry, people, etc.
Easily fits in your hand to be thumb-operated. The register advances by one digit, up to 999, each time the button is pressed. A turn of the side knob resets the register back to zero. It's a great tool for counting algae cells, zooplankton, fry, people, etc.
