Up to thru the 1923 catalog the Parker Bros. Single Selective Trigger was only offered on the Quality DH and above.
Parker Bros. Single Selective Trigger 1923 01.jpg
Parker Bros. Single Selective Trigger 1923 02.jpg
The next catalog I have is 1927 and by then the Single Selective Trigger was offered on everything but the Trojan Grade. A very few Remington era Trojan Grades were made with the Single Selective Trigger.
Parker Bros. put the trigger in the right trigger slot and the selector in the left trigger slot.
Parker Bros. Single Selective Trigger 02.jpg
Parker Bros. Single Selective Trigger 03.jpg
A.H. Fox Gun Co. with their Fox-Kautzky Single Selective Trigger did it the other way round with the trigger in the left slot and the selector in the right.
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