Peroxide treatment of a white or ivory 500

[bake114]

Gonna try peroxide on this 500. I think it's white but I'm not sure. It could be Ivory. Is there anyway to tell from  the numbers on the phone?

[RotarDad]

The back of the dial will have a color code.  Assuming it is the original dial, that will tell you.  Ivory will be coded 7C-50, while white will be coded 7C-58.   Based on the inside of your ear cap, I would bet white (code 58).  I treated a hard plastic '64 white one with the peroxide method with very good results, including the cords.