If we look at the duplicate checks meaning, it is the type of check which has a carbon copy underneath the original check. These types of a check are more secure because they keep the record of who you paid, how much and when you paid, without requesting duplicate data from the bank or on the register. But to make a duplicate on the carbon paper, one must press hard against the top check while writing. It will provide a duplicate of each check. When the writing is finished, the data is easily exchanged for the duplicate structure beneath. The duplicate checkbook is bulkier than the single one because there are a double number of pages. But there are always fewer numbers in a box than single checks due to the thicker checkbooks of duplicate checks. These are also more expensive than single checks.