Blox Racing 3" Composite Velocity Stack w/ Shorty 5" Filter and silicone coupler

This kit includes:

3 inch Velocity Stack x 1

5" tall air filter x 1 (short version)

silicone coupler with clamps x 1 

Dimension:

3" composite velocity stack (3 inch O.D. on intake pipe side, the smaller end)

6" O.D. on the Air horn side 

The Blox Racing 3 inch Velocity Stack is a trumpet shaped piece where one would attach to a vehicle's air intake.  This velocity stack act as an air flow smoother, it allow smooth and even entry of air to enter at high velocities into the air intake's flow stream to create a more even air flow that fills the entire pipe area versus air flow without velocity stack which enter the flow area pinched down.