The contact key can be used to open and close an electrical circuit. The contact key is mounted on a 3" x 4.5" x 3" black acrylic base and has two binding posts to connect to an electrical circuit. The key is made from plated metal with an insulated button. This tool is often used with a Wheatsone Bridge.
WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information go to .
Our products are not toys. Use in a laboratory or educational setting only. Not for children 13 and under.