the straight duct is empty in it you can cut it      lenght 62mm width 19 mm height 14mm

the corner  upside down is full                           lenght 23mm width 19 mm height 23mm

the side corner is full                                          lenght 23mm width 23mm height 14mm

when you buy  1 set  its for 3 piece  ... it can be changed with  the piece you need if you want more set

and you paid the shipping only one time nothing matter how many part you take