This is a new unused (less than 6 years since manufacture) 2 milliwatt Helium Neon Laser Tube that meets the following specifications:

Melles Griot Part #: 05-LHP-122
Output Power: 1.8 to 2.6 milliwatts
Wavelength: 632.8 nm RED
Polarization: Linear >500:1
Spatial Mode: >90% TEMoo
Beam Diameter: 0.6 mm
Beam Divergence: 1.3 mRads.
Beam Exit: Cathode end of tube.
Longitudinal Mode Spacing: 687 Mhz
Operating Voltage: 1750VDC with 68K ohm ballast resistor.
Operating Current:  5.5 to 6.5mA
Start Voltage: <10 KV
Dimensions: 8.99" (228mm) long x 1.45" (36.8mm) diameter

Each laser is tested and the output power is measured, prior to shipping. This is a top-quality HeNe tube. We've been in business for over 30 years and have sold thousands of HeNe lasers. Nothing beats having a new quality-built tube. The shelf-life on these Melles Griot tubes is indefinite.