uxcell 20 Pcs Amplifier 4mm Banana Socket Binding Post Connector Adapter Product Name : Binding Post;Thread Dia. : 5.5mm/ 0.22" Fit Banana Connector Dia. : 4mm/ 0.16";Overall Size : 15 x 11mm / 0.6" x 0.43" (L*Max.D) Main Material : Metal,Plastic;Main Color : Red, Black,Silver Tone Net Weight : 40g Package Content : 20 x Binding Post