WGGE Banana Plugs Audio Jack Connector, 24k Gold Dual Screw Lock Speaker Connector for a lifetime of use, with a crystal clear signalDouble screws, when properly fastened, are said to be as effective as soldering, but clearly with much less hassleMaterial:Pure Copper, gold plated, Pure copper made, non-magnetic.Accepts wire size up to 4mm. Accepts 8AWG to 20AWG speaker wireDouble screws locking, no soldering. High qualityHandling and shipping Usually ship within same business day if paid before 14:00 PST (excludes weekends and holidays)