This is a replacement JQ Products 5-Hole 1.4mm Shock Piston Set, and is
intended for use with JQ Products THE Car. Different size holes produce
an effect known as “pack”, which affects how quickly the shocks respond.
Smaller holes increase the pack of the shock, which will slow down the
compression and rebound. These are better for smooth tracks with
big-jumps and are not recommended for rough tracks. Larger holes decrease
the pack of the shock, which will make the compression and rebound
faster, making them a better choice for rough tracks.