Steel freeze plugs rust from the inside out and then let go, usually somewhere inconvenient. Brass does not corrode the same way, which is why it is worth replacing the whole set while the engine is apart rather than waiting for the one behind the bellhousing to fail.

Proform 66560 Brass Freeze Plug Kit Features:

• Fits 1958-1981 Pontiac V8 engines.
• Brass construction resists the corrosion that destroys steel plugs.
• Includes all necessary plugs for one complete engine block.
• Sold as a kit.