The main differences between GEOMET 500A and GEOMET 500B are in the type of lubricant and in their corrosion resistance.
- Geomet 500A mineral oil based lubricant
- Geomet 500B synthetic oil based lubricant (advantage: higher level of lubricity and better adhesion to the nut)
GEOMET 500A has a corrosion resistance of 600 hours or greater, while GEOMET 500B has a corrosion resistance of 1000 hours or greater.
Both coatings are zinc-aluminium flake coatings, but the 500B has a thicker layer and is more resistant to corrosion. Additionally, GEOMET 500A is available in a variety of colors sometimes, while GEOMET 500B is generally only available in silver.