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Due to COVID-19 and heavy order volumes processing and shipping times are currently being delayed.


HK HK 81000077

Product Code : 642230259300


Mfg Item #: 81000077


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The MR556A1 Upper Receiver Kit includes a complete upper receiver/barrel assembly bolt carrier assembly buffer and buffer spring allowing most high-quality 5.56 mm AR-style rifles to be retrofitted to HKs pusher rod system. - Complete MR556 Upper Receiver/Barrel Assembly HK 16.5 inch cold-hammer forged barrel upper receiver with forward assist extended convertible charging handle HK Free Floating Rail System handguard - Complete MR556 Bolt Group Assembly - Tungsten Filled HK Proprietary Buffer - HK Proprietary Buffer (Action) Spring

Determined at checkout.