HK Army provides a concise overview of the extremely limited Speedsoft HPA M4 Build, a collaboration with Monk Customs. This build features a Polarstar F2 Engine and FCU, a Retro Arms M4 Aluminum HopUp Chamber, and a Synrgy Monk X HK Upper. It also includes a Synrgy Monk X HK Hand Guard, an Aluminum Back Cap, and a Lower. The build is further enhanced with Synrgy Hostile/HK Lazer Engraving, Monk Custom Cerakoting, and a 6-inch Monk Carbon Fiber Barrel.