There is only one type of cover for hardbacks. You will need two, one for each cover of the book. Piace the first cover on the work surface and insert one cover of the book.
 
Turn the switch to OVERPOWER. Insert the excess part at the top edge of the book into the slot and press the lever for three seconds to weld and trim. Repeat the operation for the side edge
Place the second cover on the work surface and insert the other cover of the book. Insert the excess part at the top edge of the book into the slot and press the lever.
Repeat the operation for the side edge. Now, weld and trim the spine by inserting both covers into the slot.
Always with the switch in OVERPOWER position, press the lever while holding the book in position against the stop.
Before making the final trim, make sure that cover is properly positioned to guarantee a tight fit.

Here your protected book!.