The kit include 10pcs photoresistors and 10pcs phototransistors.

The photoresistors have negative brightness coefficient of resistance. These are compact and also very thin so they can fit almost anywhere that

you need them installed.

Phototransistors are solid state light detectors that possess internal gain. This makes them much more sensitive than photodiodes of comparably

sized area. These devices can be used to provide either an analog or digital output signal. This family of detectors offers

the following general characteristics and features:

Low cost visible and near-IR photodetection

Moderately fast response times

Usable with almost any visible or near infrared light source such as reds; neon, fluorescent, incandescent bulbs; lasers; flame

sources; sunlight; etc.

Same general electrical characteristics as familiar signal transistors (except that incident light replaces base drive current)