I believe that Whiz only made two styles of the counter display units, the Liquid Radiator Stop Leak and the White Rubber Patch Outfit. I have only seen a couple of the latter in the last 20 years. If it is similar to the patch outfit then it should have a back door which appears missing on yours. I have seen the liquid radiator unit in the Whiz literature but never one in a collection or for sale, so it may be rarer. I would say to a Whiz collector it would be worth $300 to $450.

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