silver, a copper-nickel-zinc alloy more commonly used for flutes, for the bodies of some saxophone models. For visual and tonal effect, higher copper variants of brass are sometimes substituted for the more common "yellow brass" and "cartridge brass." Yanagisawa made its 902 and 992 series saxophones with the high copper alloy phosphor bronze to achieve a darker, more "vintage" tone than the brass 901 and 991 models. Other materials are used for some mechanical parts and keywork. Buttons where the fingers contact the keys are usually made from plastic or mother of pearl. Rods, screw pins, and springs are usually made of blued or stainless steel. Mechanical buffers of felt, cork, leather, and various synthetic materials are used to minimize mechanical noise from key movement and to optimize the action of the keywork. Nickel silver is sometimes used for hinges for its advantages of mechanical durability, although the most common material for such applications has remained brass. Manufacturers usually apply a finish to the surface of the instrument's body and keywork. The most common finish is a thin coating of clear or colored acrylic lacquer to protect the brass from oxidation and maintain a shiny appearance. Silver or gold plating are offered as options on some models. Some silver plated saxophones are also lacquered. Plating saxophones with gold is an expensive process because an underplating of silver is required for the gold to adhere to. Nickel plating has been used on the bodies of early budget model saxophones and is commonly used on keywork when a more durable finish is desired, mostly with student model saxophones. Chemical surface treatment of the base metal has come into use as an alternative to the lacquer and plating finishes in recent years. Mouthpiece and reed The saxophone uses a single-reed mouthpiece similar to that of the clarinet. Each size of saxophone (alto, tenor, etc.) uses a different size of reed and mouthpiece. Most saxophonists use reeds made from Arundo donax cane, but since the middle of the twentieth century some have been made of fiberglass or other composite materials. Saxophone reeds are proportioned slightly differently from clarinet reeds, being wider for the same length. Commercial reeds vary in hardness and design, and single-reed players try different reeds to find those that suit their mouthpiece, embouchure, and playing style. Mouthpiece design has a profound impact on tone. Different mouthpiece design characteristics and features tend