Model SMC D-H7A2 Three Wire Proximity Switches with 6 ft. leads     
* 4.5 to 28V DC operation PNP output     
* units have red indicator light, ON when activated     
* Items are used - have been tested - with 90 day Warranty     
http://www.smcworld.com/2002/bp_e/pdf/2503_029.pdf     
Price $14.00 ea. (2 available)