Bananenstecker

Bananenstecker, or banana plugs, are a type of electrical connector commonly used to terminate leads for audio equipment, test gear, and lab setups. The standard form is a male plug with a cylindrical contact, typically about 4 millimeters in diameter, that fits into a matching banana jack. The plug is usually mounted in an insulated handle, and the contact is often gold- or nickel-plated for durability. The plugs are not inherently polarized; polarity is indicated by color coding on the attached leads rather than by the plug shape.

Construction and variants: Standard banana plugs come in several variants, including stackable designs that allow multiple connections on a single jack, locking types for a more secure fit, and shrouded (insulated) versions to reduce the risk of accidental contact. There are also smaller 2 millimeter variants used in some older or specialized equipment. Common practice is to color-code leads (red for positive, black for negative) to indicate polarity, although the plug itself remains physically symmetrical.

Usage and compatibility: Bananenstecker are widely used for loudspeakers, power supplies, battery testers, and other test equipment. They enable quick, tool-free connections and are compatible with most 4 mm banana jacks found on amplifiers, receivers, and bench instruments. The rating for voltage and current depends on the specific design and manufacturer; standard consumer versions handle typical low- to moderate-power applications, while high-current variants exist for demanding setups.

Safety and standards: To prevent short circuits and accidental contact, shrouded or insulated designs are recommended in environments with exposed connections. The 4 mm banana form remains a long-standing, widely accepted standard in many countries for both consumer and laboratory use. See also banana jack, test lead, and speaker connector.