10Pcs Black and Red 4mm Banana Jack Socket Female Adapter Panel Mount Binding Post for 4mm Banana Plug Connectors

Good quality

These jacks are a little more compact than Pomona, including the plastic shroud - which could be space saving for busy panels. The outer thread is separate from the inner barrel (the reviewer who wrote they aren’t insulated is wrong) - they are separated by the plastic (polyamide) sleeve from the jack entry down to the solder tab - the two do not touch. In other words, you can install these in metal chassis, without needing a stepped plastic spacer - another difference from Pomona type jacks. There is also a proper spring washer, not a toothed one.An icing on the cake is that these jacks also have very tight tolerance - inserting plugs is a little tougher, but the connection quality is excellent.With Pomona stuff getting dearer by the year, these Bei Qian-branded jacks are a great substitute which also happens to be an excellent quality and all around value. I’ve had good experience with all banana plugs and jacks from this brand, and hope they keep up the quality.

Came as described

Robustos y de muy buena calidad. Se pueden realizar las conexiones o derivaciones con estos conectores hembra con seguridad en la continuidad eléctrica. Muy confiables

Used in a DIY etching machine and works very well.

These appear to be well made. I have not installed them yet, but thought I would provide some additional information on the parts I received (as of December 2022).Comes with a washer and nut for mounting to a panel. The 4mm barrel appears to be machined from solid metal, unlike some other jacks that use sheet metal formed into a 4mm round barrel shape.Overall length is 28.5mm. Depth below panel is 25.5mm. Diameter of top face is 10.6mm. Diameter of mounting hole is 8.0mm. Diameter of wire solder hole is roughly 1.5mm.