top of page

This Bore-Up, double o-ring piston head is machined from duralumin EN AW 6012 T6.


Nine holes are drilled on the front side to allow the negative pressure to quickly equalize, reducing friction on the rear stroke, and helps expand the o-ring on the forward stroke. 



  • Perfect sealing
  • Bore-Up design increases available air volume
  • Axial ball bearing for easy spring rotation
  • Sleek surface