Hick

In the early 1980s, a 13-year-old girl named Luli McMullen (ChloÃ« Grace Moretz) lives with her alcoholic parents, Nick and Tammy (Anson Mount) (Juliette Lewis) in a hick town in Nebraska. And Luli receives a revolver as a gift for her birthday. While painting her nails, Luli sees a commercial for Las Vegas. Upon gathering what she needs and her revolver, Luli runs away from home. She hitches a ride from Eddie (Eddie Redmayne), an erratic drifter with a damaged leg and asks him to take her to Las Vegas. They argue and she responds by leaving the car. Eddie drives away. She then convinces another passerby, Glenda (Blake Lively) to give her a ride.
Glenda takes Luli to the home of a man named Lloyd (Ray McKinnon), with whom Glenda is involved on a criminal level. Luli then discovers Eddie works for Lloyd. Eddie tells Luli that Lloyd and Glenda want to be alone so he takes her to a bar. Eddie is interrupted while hustling pool by Luli and when his hustle fails, the man that he was hustling makes a deal with Eddie. The man then follows Luli into the ladies room to rape her. She fights him and after a time, Eddie comes in and savagely beats the man to death delivering a final blow with a sink.
As they leave the bar, Eddie says that Glenda has asked him to take Luli to a motel to meet Glenda because she got in a fight with Lloyd. At the motel Eddie gets drunk and tells Luli that Glenda actually gave him a thousand dollars to take her off Glenda's hands. Frustrated, Luli goes outside where she meets a young guy named Clement (Rory Culkin) with whom she has a nice time playing a drinking game. Eddie interrupts them in a drunken rage and the two leave the motel.
Luli tells Eddie to pull over and leaves the truck despite his begging her to stay. Eddie then gets out of the truck and begins to follow Luli. She turns and sees him. Eddie angrily chases her into a Corn field, he grabs her and tackles her to the ground. Eddie then rapes Luli offscreen.
The next day, Luli wakes up later in a strange place to find that she is barefoot, her arms tied to the bed, her ankles tied up, dressed differently, and with shorter hair which has also been dyed black. Luli then screams at her predicament and shouts for help. Eddie arrives with flowers, he unties her and professes his love for her, and he promises her that he will never rape her again. They are interrupted by the landlord Beau (Alec Baldwin) who asks Eddie how long he needs the room and then leaves.
The next day Luli, tied up again, wakes up to find Glenda in the room. After planning their escape, they are caught by Eddie who accidentally shoots and kills Glenda. Luli picks up the gun and kills Eddie. Luli then knocks some stuff onto the ground before falling to the ground. Later, Beau comes in to find only Luli still living upon also finding Eddie and Glenda dead. He then feeds Luli eggs, and he talks about his sister and how "she always wanted a daughter," insisting that Luli "look her up."
Beau then implicitly drives Luli to the bus station. Her plan is to reunite with her family. After she calls them, she realizes that it will be more of the same back home. While on the bus, she looks through her notebook of drawings and finds a note from Beau reading "Dear Luli, in case you change your mind" on a picture he drew himself of his sister's home in Los Angeles with her address written on the picture. She manages to get off by telling the bus driver that she needed to take her medicine. Once off the bus, Luli removes her sandals to carry them and runs barefoot all the way back to the bus station. Once back at the bus station, she gets a bus ticket to Los Angeles to head to where Beau's sister is living.

Question: What is used to deliver the final blow to the man in the bathroom?
Answer: A sink is used to deliver the final blow.