The 81634B is a 800nm-1700nm -110dBm to +10dBm 2 channel optical power sensor module for the HP 8163A, 8163B, 8164A, 8164B, 8166A.
Keysight 81634B Optical Power Sensor Module, 800-1700nm
Please give us to call at 866-409-0400 to discuss when you can expect this product back in stock.
Sensor element: InGaAs (dual) Wavelength range: 800 – 1700 nm Power range: +10 to -110 dBm Thermally stabilized (cooled) and hermetically sealed detector with glass window