SiegeTek make the strongest AEG gears on the planet.
This is the latest generation (Gen 4) of Chromoly gears from their factory, case hardened for extreme durability. This Spur Gear features a smooth coating that retains lubrication very well and a thicker profile for increased reliability. 
 
Fully CNC machined and expertly finished, this gear will last for years to come in virtually any setup you could build.
For absolute strength and reliability, nothing else compares.