Product description: Material:copper Color:black,red Size: Length:42mm Bottom diameter:13mm Hole diameter:4mm Thread length:14mm Weight:6*13g Package includes:6*amplifier copper binding post (3*red, 3*black) High Quality Material: The speaker binding post is made of high quality copper. It is corrosion resistant and conductive, ensuring stable current transmission. The audio binding post is not easy to oxidize and rust with long service life. Protective Shell: The plated audio terminal has a transparent ABS shell. The shell can protect the copper, the main material of the terminal, very well. It is insulated, resistant to high temperatures and corrosion. The binding post connector shell can effectively extend the service life. Easy to Use: The speaker terminal amplifier is very easy to install. Simply connect the threaded end of it to the stereo to be used. The copper binding post has two colors black and red. It allows you to easily distinguish the positive and negative terminals on the terminal block. Widely Applicable: The binding post connector is ideal for use in an audio amplifier. The plated speaker audio terminal is suitable for 4mm lantern banana plugs, 4mm four-leaf banana plugs and stripped cables. Package Included: There are 6 copper amplifier binding posts in total (3 red, 3 black). 4 binding posts can meet your needs. You can keep the other two in reserve to replace the old terminals.