Winters Quick Change Gears are constructed from SAE 8620 Steel, Crown Cut, 1-3/8" Wide. 

Specs:

Teeth: 24/25

4.11 Gear Ratio: Low 3.95 High 4.28

4.12 Gear Ratio: Low 3.96 High 4.29

4.57 Gear Ratio: Low 4.39 High 4.76

4.86 Gear Ratio: Low 4.67 High 5.06

To see other gear sets available, check out the Winters Quick Change Gear Chart