{"product_id":"hk-mr556-upper-receiver-kit-9-mrs-handguard","title":"HK MR556 UPPER RECEIVER KIT 9 MRS HANDGUARD","description":"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 HK's 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","brand":"H\u0026K","offers":[{"title":"Default Title","offer_id":46273614741643,"sku":"HK 81000077","price":2013.7,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/8581\/8251\/files\/296572415.jpg?v=1776921121","url":"https:\/\/taktactical.com\/products\/hk-mr556-upper-receiver-kit-9-mrs-handguard","provider":"Taktactical.com","version":"1.0","type":"link"}