The classic Savile Row suit features adjustable side tabs, little belts made of the same fabric as the trousers, on either side of the waistband. They eliminate the need for a belt, and they look better with braces than trousers with belt loops do. Usually, these tabs are found only on bespoke clothing, but they can also be had on made-to-measure clothing from certain manufacturers, including Oxxford, Brioni and Battistoni. Some better men's stores, such as Barneys New York or Bergdorf Goodman, will create them for you on other brands if you request it. Bergdorf Goodman has them on its own custom line. Incotex offers such slacks without suits in Super 150s wool (212-691-5100); they're pricey, but you'll save money on belts and braces.