What 3 objects can be used to represent the main themes in fight club?

Liposuctioned Fat: Note the Irony

Tyler uses fat left over from cosmetic procedures to make soap. He even goes as far as to trick Marla's mother into sending her own fat. This idea is significant as it is Tyler's way of playing on people's vanity. He uses fat they discarded and then turns it into a luxurious soap that they buy right back.

Tyler's Chemical Burn

Everyone who comes into contact with Tyler has a chemical burn. It is a kiss mark seared into the back of people's hands. Tyler uses lye to burn the skin.

Airports

The narrator spends most of the book going back and forth between the country's many airports. They represent another part of his single-serving life.