Materials & Finish
FERRULE: Hardened carbon steer, 
  zinc plate, chromate plus sealer. 
  
  
SPRING (internal component, not shown):  300 Series 
  stainless steel, passivated.
  
  
KNOB:  6000 Series aluminum, natural or black 
  powder coated. 
  
  
SCREW:
   Slot, Phillips, TORX®, and Phillips/Slot 
  Combination: 400 Series stainless steel, passivated, bright or black 
  powder coated (screw head only). 
  
TORX®/Slot Combination: Hardened carbon 
  steel, zinc plate, chromate plus sealer or zinc plate, chromate plus black powder 
  coating (screw head only).