Up for sale is my B&W Tek bench, grating, and mirror set which is just what you see in the first picture. The grating is 1800 Gr/mm with a blaze wavelength of 500nm.  One thing I especially like about this set is that the focusing mirror comes with adjusting screws so it is much easier to align.  The graph in the last picture is an efficiency curve of what one can roughly expect out of this grating.  If you only need the optics without the bench, please go to:

https://www.ebay.com/itm/143969241357

Thank you. 

I have been an eBay member since 2001 with excellent positive feedback.  If you have any questions, or are interested in buying these in volume quantity, please scroll up and click "contact seller".  Thank you.