New or used optical & electronic test equipment

81000AF Filter Holder - this threads between the head and connector/bare

fiber adapter and holds a 1" diameter, user-supplied filter in the beam.

The user can place any type of 1" filter here, including filters for attenuation.

However, most attenuation filters are the neutral density type,

which have a strong wavelength dependence of attenuation

(which the user would need to characterize).