H&K Heckler & Koch

H&K HK MR556 A4 Gas Block - Complete Factory HK MR556 A4 adjustable gas block ideal for switching between suppressed and unsuppressed firing.   Compatible With: HK MR556 A4 Nefarious...

H&K HK MR556 A4 Gas Block - Incomplete The H&K HK MR556 A4 Gas Block is a high-quality, precision-machined component designed for the MR556 A4 rifle. It houses the gas system that directs gas...

Heckler and Koch Hammer for HK MR556 Semi-Auto rifles Factory-original German steel hammer for MR556 A4 rifles. Designed as a direct replacement for worn or damaged hammers in MR556 A1 and A4 trigger...

H&K MR556 A4 Hammer Spring Genuine H&K hammer spring for the MR556 A4. Compatible With: HK MR556 A4

H&K HK MR556 A4 10" Handguard This 10" factory H&K MR556 A4 handguard offers a lightweight, free-floating design that enhances accuracy and provides rock-solid mounting for accessories. Made...

H&K HK MR556 A4 13.4" Handguard This handguard is expertly engineered for precision and adaptability, featuring a robust Picatinny rail at the 12 o'clock position that guarantees seamless...

HK MR556 A4 Operator's Manual Official operator's manual for the HK MR556 A4, covering function, maintenance, and safety procedures.

H&K Heckler & Koch MR556 Upper Receiver Kit A4 -11″ - M-LOK  This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be...

H&K MR556 A4 16.5″ 5.56 M-LOK Upper Receiver Kit This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted to HK’s piston...

HK Heckler and Koch A4 Complete Upper with Full Auto Ejection Door for HK MR556 The HK MR556 A4 Complete Upper is a superior factory assembly that comes fully equipped with a forward assist and an...

HK MR556 16" Complete Upper Barrel Factory HK MR556 16" barrel, complete with a factory-installed barrel nut, gas block and flash hider. Every component is brand new and meticulously crafted,...

H&K MR556 Slimline Barrel, 16.5" Genuine HK MR556 Slimline 16.5" Barrel.  Non-chrome-lined for match accuracy. Compatible With: HK MR556