Products in this family are ancillary to or supportive of barrel-style connector products, including things such as mounting hardware, dust covers or caps, insulators, and similar items. Note that in this case, both common versions of the barrel plug concept are referenced; both the cylindrical connectors having multiple connection points along their length most commonly found on headphones, and the tubular style with concentric inner and outer contacts, commonly found on small wall mounted AC-DC converters.