60 Pieces Clip-on Ferrite Ring Core RFI EMI Noise Suppressor Cable Clip for 3mm/ 5mm/ 7mm/ 9mm/ 13mm Diameter/Video Cable Power Cord (Black)

Good variety pack for filter chokes. We deal with RFI occasionally on Field Day, and you never know what gauge of wire will need shielding. Throw a few of each size in a bag and you're ready for anything. Holds secure, but is usually pretty easy to release if you want it off.

Great product, I was having RFI issues on my ham radio setup, primarily on digital modes, as my USB cable is not shielded very well. Using 2 of these, 1 on each end, with 1 coiling I was able to mitigate all of the RFI issues which kept causing WSJT-X to crash, now to find out where that RFI is coming from in the first place!

Maybe not kill all the 'QRM' hash noise in your house, but certainly squash it down a bit.So much radiation, so few ferrite beads -at low price, to go around...We all are literally swimming in a soup of broadband electrical emissions.I've bought TWO of these kits already, and thinking about another 1 or 2.Go around and count how many USB cables, wall warts, phone chargers, wireless speaker power packs, tv's, modems, laptops, AM/FM receivers, etc you have in your house -anything that is electronic, to get an idea of how many beads you might need.These do work, but you will need a SCAD of these to squash the dozens of sources of RFI in proximity to your ham rig or AM/FM radio.The problem is, the great providers of this precious material are greedy and miserly about giving the larger sizes. Fifteen bucks for a single fat 1" ID ferrite toroid sucks!Another of my big gripes is these [far Eastern] guys do not tell you what the material type is (43, 61 or ???) and no specification of attenuation versus frequency performance.You literally do not know what you are buying OTHER than a bag full of various sizes.Given the above, what we all really need is larger sizes, and MORE of them. More than just 5 or 6 half-inchers in a 'kit'.Why the larger sizes?Because, to squash the lower frequencies (< 50MHz) -a greater bandwidth, you need to either add multiple ferrite beads (spend a LOT more $$), or 'wind' each bead at least TWICE with the conductors that are radiating the RFI.Each time a conductor passes thru the bead (a single 'turn'), the attenuation is SQUARED after the first winding. The problem with this is the wire size is too big to wind more than once or twice through a 1/2" ID bead and still get it to snap shut (and it MUST be snapped shut to complete the electromagnetic attenuation effect).Each kit I used, I first used up all the largest beads -and needed more, then I started using up the successively smaller beads, but the smallest ones are almost too small to get even ONE pass of the wire thru.-a little like moving a BIG pile of rocks...you are not done until every one of the radiating conductors has at least one bead.Sorry, I vented my spleen.73

My welding rotator was rebooting every time I’d trigger the high frequency start on my TIG welder. I bought these as part of my remedial action to prevent this. Snapped them onto the power and ground lines on the DC power supply as well as a larger one on the incoming AC and it now works perfectly.

Good quality!

This review is for the Phono Stage Analog Audio enthusiast. I bought these with some skepticism but thought “what the heck”. [My System] I have an all tube analog playback system: A VPI Scoutmaster Turntable, Sumiko EVOIII Bluepoint Special High Output 2.5mV cartridge, Ming Da MC767-RD Phono Pre Amp, Pangea Audio Premier XL Phono Turntable Cable with built in ferrite rings on each end and grounding wire, Antique Sound Labs (ASL) AQ 2001 DT Pre Amp, Mogami’s top RCA interconnects throughout and a pair of ASL Hurricane DT Mono Block Power Amps with 8 KT88s in each amp. [The Problem] As you already know, eliminating phono stage ground loop and RF Interference from any system can be a frustrating task, even after attaching the perfunctory ground cable from turntable to amp/pre-amp. Before clamping these ferrite clips on I kept getting the usual annoying electrical hum, faint background FM radio station interference and the dreaded/annoying CB Radio operator chatter (and the vile unlicensed discourse that comes with it). This was the case even after having a renowned high end audio tech make extensive grounding circuitry modifications on my Ming Da. [Methodology] I clipped a ferrite ring to each end of the grounding wire (2), each end of the left RCA and right RCA cables going into the phono preamp (4) and each end of the left RCA and right RCA cables going out of the phono preamp (4) and one on each end of the RCAs out of the ASL Pre Amp to the Mono Blocks Power Amps (4) for a total of 14 ferrite rings. [Outcome] To my pleasant surprise, when I turned everything back on, all the aforementioned noises above were gone! Even when I cranked the ASL Preamp gain full tilt, the radio stations (CB and FM) were nowhere to be heard, even faintly. The electrical ground buzz was gone, too. All I heard, and only at super high ridiculous volumes (that I would never use in real life) was the noise from the phono preamp which is to be expected due to the inherent burden of MC/MM amplification. At normal listening levels my noise floor is so scarcely audible it’s basically gone, even before I drop the needle. [Conclusion] To my fellow analogue/vinyl enthusiasts fighting the ground loop/RF monster, I say buy these things. I never write reviews but this one was a must. Happy Listening!

Seems to help with RF in Shack. But not great.

I was getting tons of loud GPU ground loop/common mode noise via USB to my external DAC. Nothing worked, even the ground loop isolation devices.After applying one medium choke to each of the PCI-E connectors, one large choke across both, and one large choke across the aux CPU power wires (all close to the noise source, so GPU and mobo respectively) I am hearing absolutely no noise - even with Furmark. These also double as cable management clips.Put simply: the medium chokes are large enough to clip over single PCI-E power wire bundles, and the largest chokes are large enough for two PCI-E power wire bundles.Super easy to install: open and click closed.