Nikon Chroma UV fluorescent microscope filter cube. The Chroma number is 11000  and it will fit the Nikon Labophot, Labophot-2, Optiphot, Optiphot-2, Microphot and TMD inverted microscope. It comes in an original plastic filter cube case which is not pictured.

The filter specifications are:

Dichroic Mirror: 400DCLP

Exciter Filter: D360/40X

Barrier Filter: E420LPv2