Metco Valve Cover Breather for Holley valve covers

Overview:

This valve cover adapter replaces the original oil fill cap included with many popular aftermarket valve cover sets.  It is CNC-machined from billet aluminum for precise fit, and the included silicone O-ring is specially designed to prevent oil seepage at the base of the adapter.

Overview

• 10AN Valve Cover Adapter
• Fits Aftermarket Valve Covers with 1 5/16"-12 Screw-in Thread, Including Holley Cast LSx Covers
• An Original Metco Motorsports Product!
  
• Total adapter length is about 1.8", with about 1.25" above the flange of the cover. 
• The top of the adapter is machined to accept a #10AN hose end to facilitate the installation of a custom crank case evacuation system, PCV system, or for use with a vacuum pump.