For example, accommodation invoices, catering invoices and so on. The effectiveness of the water bill: the water bill belongs to the enterprise in order to better carry out the internal control, demand for consumption vouchers, while the invoice is the enterprise pre-tax deduction vouchers. Water bill belongs to the enterprise homemade vouchers, in fact, the effectiveness of the above is much smaller. Of course, it is also easier to fake, even if the fake will not be subject to any actual punishment. The role of the water bill according to the invoice, enterprises do not have to water bill, but in some special projects in order to strengthen internal control, the role of the water bill can not be ignored. Generally speaking, the invoice can not show the specific details of consumption, only when the need for water bill. After all, the invoice now also need to open specific details. However, there are still some items can not be issued specific details, in this case, the role of the water bill also appeared. In fact, in the final analysis, the water bill is to let the enterprise know whether these items are in accordance with the provisions. Let's say that the enterprise's business personnel in the hospitality, is a little bit of inappropriate dishes. Or that the enterprise in the accommodation, produced other consumption items and so on.