I like the "flip-up" covers but I usually don't hunt with them in the closed position. Also, if the covers are closed (due to inclement weather conditions or whatever) and a shot presents itself when the little noise created in opening them might have big (negative) consequences in terms of alarming the game, your "second" hand can be employed to help muffle the unwanted sound by retarding the opening action of the spring-loaded covers. I do agree with those who argue that you should never compromise the "stock-weld" afforded by properly low mounted rings/bases just in order to accomodate scope lens covers.
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