Agilent 1260 detector

You'd need to be more precise. 1260 degasser doesn't mean much. What's the model number, is it a standalone module or is it an internal degasser on a pump? Most importantly: Which lens? An optical bench as part of a degasser???

Agilent 1260 DAD for infinity II

I need the part number of all the lenses in the detector

I mean detector, sorry 

For the 1260 infinity II DAD model G7115A 

G1315-65201 Source lens (achromat)

G1103-68001 Coupling lens assembly

Is this what you are looking for?

Yes that is it thank you, what about the rebuild lens in the flow cell is it replaceable and have a part number? 

Have a look at section 10 of the user manual for the rebuild kits for the different flow cells that fit this detector.

It's not a lens, but a window.