2018/1207 - An article made of hot rolled non-alloy steel with a coating made of nickel silver alloy. It is presented in the shape of a round cap (diameter 2,7 cm) with slightly lowered centre, turned down into a hole, with small air gaps inside the turned down part. The cap is connected to a hollow threaded shank (diameter 0,5 cm). The total length of the article is 2,5 cm. The article is designed to be used as a tuning element in a specific bandpass filter (the bandpass filter is used in cellular network - The Trade Hub