Speaker Banana Plugs (Connectors) Nakamichi Banana Plugs N0532E. The speaker bananas are gold-plated 24K for maximum clear signal transmission. The connectors are made of high-purity copper, non-magnetic. Thanks to the large contact area, the hollow banana plug with a strong pre-sprung lamella ensures 100% contact for a long time. Suitable for cabling up to 4-5mm in diameter (inclusive).