This muzzle brake has 6 slots to disperse the gasses. The muzzle brake is chambered for the 9mm platform and CNC machined out of solid 4150 Steel with a high quality Black Phosphate finish.The serrations are intrusive and can be used to break glass, doors, and other non-lethal methods. All ports are vertical to disperse the pressure gasses and provide minimal pressure blast to the operator
Item detail:
  • CNC machined from solid 4150 steel construction
  • Phosphate finish
  • Serrated design with 6 slots
  • 1/2x36 thread pitch
  • Caliber: 9x19 Lugger
  • Finish: phosphate
  • Weight: 2.0 oz.
  • Length:1.075" 
This muzzle brake does not include the washer

http://tacticalsolutionsgroupllc-com.3dcartstores.com/-AR-9-PINE-CONE-MUZZLE-BRAKE-9mm-_p_136.html