High quality 9" acrylic dome, with 3/4" flange. Great for many uses. Could be used as a pet window in a gate, a kid window in a playground, a cover to protect a surveillance camera (may possibly interfere with motion detection), a cover to protect an all-sky camera, a cover for a skylight (if sealed sufficiently), and anything else you can think of. Note that the shape is half a sphere and that two put together could make a nearly perfect whole sphere.

4th photo demonstrates 2 domes making sphere, but only 1 dome per purchase. UV resistant and approximately 7/64 of an inch thick. Clear, high quality plastic. 9 inch diameter (not counting flange), 4.5 inch height, and 3/4 inch flange with pre-drilled holes. Useful for many applications.