The Infrared Optical Sensor has an invisible infrared light source that is ideal for working up to 0.5 inch (12 mm) from high-speed equipment or other applications providing only contrasting  light and dark surfaces or beam interruption by solid objects as small as 0.039 inch [1 mm]. The sensor is housed in a threaded 303 stainless steel tube and supplied with a 90 degree angle aluminum-mounting bracket and two M16 jam nuts.  The IRS is supplied with an 8 foot [2.4 m] cable terminated with a 1/8 inch [3.5 mm] male stereo plug (IRS-P) or 4 tinned wires (IRS-W). An optional 25 foot [7.6 mm] extension cable EC-25P is available with a female socket for the plug on one end, and a 1/8 inch [3.5 mm] male stereo plug on the other.
The IRS-P will work directly with all Monarch Tachometers (PLT200), Deluxe Nova-Strobes (dax, dbx, DBL) and Phaser
Strobes (pbx, PBL).