The two black lines tattoo is a tattoo that is used as a symbol for a bond of friendship. This tattoo is often inked on the inside of the wrists and is believed to signify an everlasting friendship. The two vertical lines are said to represent two people who are united in friendship and are determined to remain together no matter what. The black colour is said to signify strength and eternal unity, while the two lines hint at trust and loyalty. The two black lines tattoo is a unique and meaningful way to commemorate a special friendship.