HS5D-11ZRN - 

The smallest in their class at just 30 x 30 x 91 (mm), IDEC now offers compact HS5D Interlock Safety Switches available with up to three contacts. These switches provide a high-quality, space-saving product at a competitive price. HS5D safety switches are the first in their class to allow you to monitor if the head is separated from the body. Some interlock switches on the market have configurable heads, but none except the HS5D have a contact that allows easy identification of detachment of head, providing an extra safety measure. HS5D Switches are available with metal or plastic heads. The metal head can prevent damage and can also be rotated eight different ways based on actuator entry, providing mounting flexibility for each unique situation.