Practical and convenient: these banana keystone jack inserts with red and black rings provide users with a secure and fast quick way to connect a speak cable to your audio devices, bringing a lot of convenience to every user. Quality keystone insert: the binding post terminals are gold-plated, feature chemical resistance, heat resistance, non-toxic and tasteless; When upgrading or remodeling, the solid snap-in structure of the banana keystone jack inserts can be removed and relocated easily. Adjustable thumb screws: the keystone audio binding post has adjustable thumb screws, so that it can be applied with banana plugs or bare wires; Keystone insert with a ring label connector on both sides provides a neat installation, suitable for home and office. Compatibility: binding post keystone jack inserts with rings can work with most standard white keystone wall plates or panels. Colour: as shown Material: metal Package Contents: 12 * banana jack keystone inserts (6 pairs) Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.