Two tools are included with 010 Editor that make inserting or filling blocks of bytes easy.

Click the 'Edit > Insert Bytes...' menu option to access the Insert Bytes tool. The current cursor address will be displayed in the Start Address field. Enter the number of bytes to insert in the Size field. The address and size can be displayed in hex or decimal formats by clicking on the Hex or Decimal radio buttons. The value of the bytes to be inserted can be controlled in the Byte Value box by entering a value in the Hex or Decimal fields. Note that the value is automatically converted between hex and decimal formats as a number is entered in either field. Click the OK button to insert the bytes, or the Cancel button to close the dialog without making changes. Note that bytes cannot be inserted into a drive or a process.

Click the 'Edit > Fill Bytes...' menu option to access the Fill Bytes tool. If any bytes are selected in the editor, the starting address of the selection will be displayed in the Start Address field and the number of bytes selected will be displayed in the Size field. Otherwise, the current cursor position will be listed in the Start Address field and the last number of filled bytes will be listed in the Size field. A Byte Value can be entered as when using the Insert Bytes tool. Click OK to set all the bytes specified by the Start Address and Size to the given Byte Value. The Cancel button will close the dialog with no changes.