Unit Type: You can allow to add Unit Type for the particular Product. A default will be used as Hours.
You can also add default quantity
Taxable: You can make the product as taxable and non-taxable.
Default Tax: You can set default taxes for particular tasks. So when we will use the same task in Invoice/ Estimates/ P.O. and Credit Note then for that task line, a tax will be set according to selected task.