Item #9850-White 5" AC grille - Always Open with Rotatable Louvers. Has a 1-7/8" deep spud on the back for ducting that measures slightly over 5" in diameter (5-1/8"). Outside diameter of mounting flange is 7".
These warnings are not an indication that these products are violating any safety standards or regulations.
However, as our products might be sold in the state of California, we are legally obliged to inform customers about the potential presence of these chemicals in our products.