This is the Team Losi Racing 12mm CNC Machined Shock Piston Set. These shock pistons are included with the 22 2.0, but can also be used as an optional upgrade for the first generation 22, 22T and 22SCT vehicles. 

Features:

• CNC Machined to closely match the tolerance of the shock body bore and the shock shaft to increase consistency and performance versus molded pistons
• Each piston has two 1.6mm holes 
  
• 2-Hole pistons give more pack without make the car 'stiffer' around ride height and while cornering
• Each Piston is milled with the numeric value of the size of each hole
• Compatible with all 22 series vehicles, as well as the TEN-SCTE