Check the listing for details. Ocean Optics HR2000 & HR4000 Spectrometer #9 H9 Optical UV-VIS-NIR Grating. Condition: Used. Listed at 59.99 USD. Up for sale is one Ocean Optics H9 grating with mount. This grating is best suited for applications between 240nm and 1600nm This grating is all set to put into your Ocean Optics HR2000, HR2000+, HR4000, QE65000 spectrometer, and many others. The nice part about this sale is that the mount in already included. You can buy the gratings from certain manufactures but they don't include the mount. Cosmetically, there could be slight imperfections in the grating but nothing that should show up in any results. Thank you. Please view the pictures of the grating marked "H9" in my pictures. It's physical dimensions are 25mm x 25mm x 9mm. The diameter of the mount is 31mm. If you need a grating for an Ocean Optics USB-2000, USB-2000+, or USB-4000, please view my other Ebay ads because the dimensions of those gratings are different at 12mm x 12mm x 6mm I have been an eBay member since 2001 with excellent positive feedback. If you have any questions please scroll up and click "contact seller".