The real distinction on quantity types can be thought of as follows. Are you entering a count of items? Like for example finished goods like 5 rings? You would probably never have 5.34 rings. 5 Rings is considered an Item Count. Or, are you entering 4.52 carats of loose stones? Or perhaps 3.48 grams of some ear clips? In this case the quantity is a measurement.

When entering a qty that is not an integer you should choose MEASUREMENT from the Qty Type Drop down just above the quantity field. For example, 4.82 is not an integer value so you should select MEASUREMENT.

When entering a qty that is an integer, it is preferred to choose ITEM COUNT from the Qty Type Drop down just above the quantity field. For example, 2 is an integer value so you should select ITEM COUNT.

If you enter a non integer value as a quantity with Item Count selected, the machine will force the value to an integer either up or down from the value you entered. This will affect calculations. That's not what you want.
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