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ProMag 40rds 9mm Magazine for Sig MPX Black. The ProMag Extended Magazine is designed for reliability and durability. It is constructed from a proprietary DuPont Zytel based polymer offering chemical resistance and temperature tolerance. Inside, a molded polymer follower works with a heat-treated chrome silicon spring to ensure proper round alignment and smooth feeding. Magazine capacity is 40 rounds and is designed to fit Sig Sauer MPX 9mm rifles. Made in the USA with high strength and durabili…
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