The WSI1201 is a circular, flat window made of silicon, with a diameter of 12 mm and a thickness of 1mm. This window is sourced from Knight Optical and is currently in stock. It is available for purchase through their website at https://www.knightoptical.com/stock/default/silicon-window-12mmdiax1mmthk.html.
This window is classified as a 'Window' and more specifically, a 'Flat Window'. It features a 'Thin Lens' shape and is uncoated. The material of this window is identified as 'silicon sal vil 1957'.
The wavelength of this window is 633, making it suitable for a range of applications that operate within this wavelength.
Please note that the window does not come with any coatings. If you require a coated window, you may need to consider other options from Knight Optical's extensive catalog.