Weinmann pads with four square sections as well as 6 and 7 bumps in red compound are familiar to me. But, this was a big surprise to see.
Here is a photo from a current eBay auction [item # 350184424789]:
I've never seen this style available in the red rubber version before. These are clearly molded with an early (1975) date designation. I wonder how long the red pads were actually produced?
Here is an informal chronology showing some examples of the Weinmann "X" type pads which I own. Weinmann very slowly, and only very slightly, evolved the shape of these pads during more than 25 years in production. Shown in this photo are the oldest on the left, newest on the right...
BOB HANSON, ALBUQUERQUE, NEW MEXICO, USA
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