You can purchase new replacement parts here:

• PISTONS for GEN1 and GEN2
  
  • 1/2-28
  • 9/16-24
  • 37/64-28 (0.578-28)

• BOOSTER CAGE for GEN1 only
• RETAINER for GEN1 and GEN2

• END CAPS for GEN1 only
  • 9mm
  • 45cal
• SPRING for GEN1 and GEN2

For threaded retainer and spacer, please see this listing for Fixed Barrel Kit. For any other parts or repairs, please contact us for instructions.