A road guardrail (also known as a crash barrier or traffic barrier) is a system designed to redirect vehicles that have strayed from the road, preventing them from impacting roadside hazards or crossing into opposing traffic.

The term "hot-dip galvanized" refers to the anti-corrosion process:

1. The fabricated steel guardrail components (beams, posts, bolts) are completely immersed in a bath of molten zinc.

2. The zinc metallurgically bonds with the steel, creating a tough, multi-layered, and uniform protective coating.

3. This coating is highly resistant to abrasion and provides both barrier protection and cathodic (sacrificial) protection, meaning the zinc corrodes first before the underlying steel.