The Browning M2HB is one of the most important weapons platforms ever designed. With the size and stopping power of the .50BMG cartridge, it is no wonder why even today almost 100 years after it was designed it remains a force in war. The M2HB Retracting Slide Assembly is exactly as it sounds, the assembly that is used to manually retract the bolt to charge the M2HB with ammunition. Each M2HB Retracting Slide Group is complete and ready for installation onto your existing M2HB heavy machine gun, or can be used on your next semi-auto M2HB build.