This is a set of two G&H mono L-type phone connectors, model RF2P NNN. G&H uses OFC (Oxygen-Free Copper) for the core material, which is said to provide less signal stress during transmission. The housing, sleeve, and nickel are all made of nickel. Compatible cable diameter is approximately 7.5mm. The current Sound House price at the time of listing is 1480 yen per piece. https://www.soundhouse.co.jp/products/detail/item/143945/ I bought these but never used them, so I am selling them unused. From a non-smoking, pet-free environment.