Oil filler/breather holes on all Speco valve covers are 1¼" diameter.
HOLDEN 149–202 VALVE COVERS An asset to any engine bay, these valve covers are made of heavy gauge steel and are triple chrome plated. Don’t forget wing nuts, hold downs and breather caps for the ultimate finish. They are suitable for roller rockers.
CHEV. 283–350 VALVE COVERS With a high rise to fit engines using roller rockers, these standard type covers are designed to clear air conditioning brackets and power brake booster. They are triple chrome plated.