To clarify.. this is Aluminum trim not stainless. The drain cleaner or oven cleaner removes the clear anodizing on the part, exposing the raw aluminum below. Aluminum is relatively easy to polish (probably not quite as simple as it looks here) however... The finished part no longer has the clear anodized coating which protects the part from oxidizing. The part will require frequent polishing to maintain that finish.
For an old part on which the anodizing has clouded (due to UV and weather) it will restore a nice shiny finish (with some elbow grease). If it is not exposed to the weather it will probably be adequate for most.
I have done this on several pieces of old original trim and have not been satisfied with the end result. It took a lot of work and several applications to get ALL the anodizing off of the parts. This is especially true if there are any grooves or relief detail on the part. The parts required significant polishing to bring them back. Any small pits in the part (scrapes, blemishes, stone chips) turn black and are difficult to polish out without abrasive work although time and buffing will make almost anything nice again.
Re-anodizing is very expensive and doesn't seem to look like the original..... I've recently recovered from the cost of NOS trim for my missing pieces.
Gary
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