Flat Rate
Just enter a single ship cost value.
Flat Rate does not mean Flat Rate per item. Some merchants commonly mistake this rate type for a 'By Items' rate type. This is not a flat rate per item. This is a flat rate. So if you have a flat rate of $10, shipping will be $10 for the product group it belongs to, whether there is 1 or 10 products from the group in an order.