High purity fluoropolymers are obtained by the emulsion polymerization process, removing essentially all ions and coagulating the polymer essentially without adding ions. The distance is measured in coarse resolution, and in fine resolution that corresponds to distance attributes. The PCB includes a removable portion that, when removed, leaves an opening that receives an RF antenna connector. A method for magnetic resonance imaging with multiple transmit coils comprises the step of exciting a portion of an examined subject with the multiple transmit coils and the step of receiving magnetic resonance signals from at least one radio frequency coil for generating images corresponding to the selected portion of the subject. The inner bearing retainer ring includes a conductive contact surface. The sliding bracket is adapted to be deposited an input unit, is movably mounted between the hinge assembly and the rail assembly and has at least one upper sliding shaft and at least one lower sliding shaft.