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All Types of MINISHELLS are loaded to SAAMI specs according to 12ga shotshells of regular size, namely 2-3/4" or 3" in length. This means that regular shells and MINISHELLS generate the same pressure in the chamber of 12ga shotguns. MINISHELLS should NEVER be used in signal/flare guns or any other firearm other than 12ga caliber SAAMI approved shotguns. Failure to comply with this may result in injury or death to the user or others.