Review on 20pcs Clip-on Ferrite Ring Core Black RFI EMI Noise Suppressor Cable Clip - Enhance Signal Quality and Reduce Interference by Justin Quinones

Unlike most of Revain's other 20-piece ferrite choke kits under $10, this kit lacks the smallest 3mm size, but offers instead there is an additional element for each of the other more meaningful sizes - i.e. 5x each of the 4 sizes instead of 4x each of the 5 sizes. I found the 7mm size to fit a standard electric lamp cord, 2 conductor 16AWG insulated lightning cord. Size 9 mm fits 2 conductors 12 AWG, in my case 12 VDC output from switching power supply. (See photo.) It would be nice to know what type of ferrite material was used to see the electrical characteristics, but 45 cents for a choke is an unrealistic expectation. For the price they appear to be well made and were shipped securely, all arrived undamaged.