They are standard at Sauer too, all of mine have it and every example I’ve seen has as well. It’s very popular and common in Suhl, many makers there had it as their standard stock pattern, Simson, Kettner etc. The example above is without a doubt Sauer. Haenel didn’t make many Mausers but I’ve seen 2 or 3 examples and they too have the typical stock pattern of the time.

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