If you want to maximize the performance of your ARM 4.0T Intake, you will want to opt for the additional Heat Shield, which separates the cold air feeding the intake filters from the hot air generated by the engine.

This will result in cooler intake air temperatures. The ARM 4.0T Heat Shield makes a tight seal to the hood, maximizing the amount of cold air ingested by the ARM 4.0T Intake system.

Note: 

Designed specifically for use with the ARM 4.0TT Intake systems:

ARM Motorsports 4.0TT Intake System (13-18 RS7)

ARM Motorsports 4.0TT Intake System (13-18 S6,S7)