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

Specs:

Teeth: 24/28

4.11 Gear Ratio: Low 3.52 High 4.80

4.12 Gear Ratio: Low 3.53 High 4.81

4.57 Gear Ratio: Low 3.92 High 5.33

4.86 Gear Ratio: Low 4.17 High 5.67

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