The Models T10, T20, and T18 are line matching U-frame, varnish-impregnated transformers. High efficiency units reduce line loss when long transmission cables interconnect amplifier and loudspeakers and when two or more loudspeakers are connected to a common amplifier source. Each unit features element-resistant components and clearly identified terminals for solder connection. All models offer a wide selection of primary and secondary impedance and power taps.