CdS Light Sensitive Resistor
The CdS is a light sensitive resistor offering a range of 160 ohm to 700k sensitivity.
A small CDS cell, great for robot eyes. Bright light resistance measures ~160 ohm and ~700K ohm for dark resistance.
These light sensitive resistors measure 4mm x 3.5mm (5/16" x 1/8") across the face with long 4cm (1.5") leads.