Miniature EMI Filters 4300 Series Tusonix Miniature EMI Filters 4300 Series are ideal for applications where small size and high performance are critical. These C configured filters can be glass sealed on either one of the ends for optimal sealing between system compartments or components. The gold plating on the press fit leads offer excellent conductivity and connective ability. The Tusonix Miniature EMI Filters 4300 series feature a small package and a large range of electrical characteristics that make them an effective solution for a variety of microwave applications.