Installation Principles: If your bare wire is too small,it could break easily if useddirectly.The wires should be installedbackwards for a secure anddurable fit.（Installation instructions are shown in the product images.） Installation Principles: If your bare wire is too small,it could break easily if useddirectly.The wires should be installedbackwards for a secure anddurable fit.（Installation instructions are shown in the product images.） 4mm Banana Plugs: Gold Plated Male Terminals for Speaker Audio Wire Pin diameter is 4mm, standard size. Plastic handle colors: red, black Stackable design: Multiple banana plugs can be connected simultaneously, allowing for multi-device connectivity.