The Standard Price is what the buyer actually pays, whereas the "Fair market value" determines what the product is actually worth. The difference between these two prices would be the tax deductible amount.
  1. Navigate to Fundraising > eCommerce.
  2. Find and edit the product.
  3. Go to Step 2.  Pricing.
  4. Set the Fair market value for this product to the same price as the Standard Price.
  5. Click Save or Next