This is a 33066FL01-520R Float Glass Plane Ruled Diffraction Grating, sourced from the reputable vendor MKS/Newport. The grating, which is 12.5 x 25 x 6 mm in dimension, is a Blazed Ruled Reflective Grating with a Sub Type of Rectangular.
The grating's physical data includes a blaze wavelength of 1000, 600 grooves, a blaze angle of 17.5 degrees, and an orientation vector of (1, 0, 0). The grating side is the front, and the order is 1. The material ID is soda lime ru clear.
The grating is coated with nwr 53-520r-1131-1sp on the front. The wavelength is 588, and the item is currently in stock, as indicated by the "weblink status" in the item data.
For more detailed information, you can refer to the vendor's website through the provided weblink: https://www.newport.com/p/33066FL01-520R