Computer/Digital RFI Solutions Ferrite filter products can help speed up digital devices by suppressing common mode current from RFI sources OR prevent digital devices from emitting RFI on its connecting cables and power supply lines. Mix 31 Store / Mix 31 Ring - Mix 31 - RFI Range: 1-300 MHz Ring - Mix 31 - RFI Range: 1-300 MHz Snap On - Mix 31 - RFI Range 1-300 MHz Snap On - Mix 31 - RFI Range 1-300 MHz Slip On - Mix 31 - RFI Range 1-300 MHz Slip On - Mix 31 - RFI Range 1-300 MHz