The white dress shirt is usually made of cotton or linen. A dress shirt has a stiff collar and it is ironed before it is worn. A bow tie is usually made of silk or polyester, and it is usually black or white. Dress pants are made of wool or polyester, and they are ironed before they are worn. A tuxedo suit jacket is usually made of wool or polyester. Suit jackets have a collar, pockets, and a silk or polyester lining. Leather dress shoes are usually made of dark-colored leather which is polished. Sometimes, a person wearing a tuxedo will also wear a sleeveless vest with buttons in the front, a black top hat, and white gloves.