![](https://s3images.coroflot.com/user_files/individual_files/613050_umbgllqjagolpufhttrmkbwkp.jpg)
Photo resistor up close.
![](https://s3images.coroflot.com/user_files/individual_files/613050_pxrecelpx7ry25jjr2o6qctn9.jpg)
Basic components are a photo resistor, LED, and shrink wrap tubing.
![](https://s3images.coroflot.com/user_files/individual_files/613050_utqvnwtfzgyi2vzdzejhwbeyw.jpg)
Place components inside shrink wrap, face to face.
![](https://s3images.coroflot.com/user_files/individual_files/613050_uu7etuadukreh8gfrl3gq32jt.jpg)
Simply apply heat with a heat gun.
![](https://s3images.coroflot.com/user_files/individual_files/613050_b68gliuvyhxykxipbyhotsutz.jpg)
Vactrol! The LED can be biased for brightness using the appropriate resistor value in series.
gLike