Basically speaking, there are 2 choices for the Amazon Fee Rates, the default is as below for all publishers.
TABLE 1 – Fixed Advertising Fee Rates for Specific Product Categories
And there is an alternative choice for any publishers about the amazon fee rates.
TABLE 2 – Volume-Based Advertising Fee Rates for General Products
Based on our experience, for customers who can bring tons of sales a month based on a heavy traffic site or site group, the alternative choice is better for more commissions.