If you're looking to take advantage of all the components available for the .300 Blackout cartridge, then the Knight's Armament SR-30 IWS Complete Lower Receiver is purpose-built to be your perfect starting point.

Thanks to the company's more than 30 years of developing premium firearm technology, the Knight's Armament SR-30 IWS Complete Lower Receiver is loaded with some of the best features available in today's AR world, including fully ambidextrous safety selectors, magazine release and bolt release. These, plus a two-stage match trigger, are all contained in a battle-ready, forged lower.

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