Toroid Ferrite Cores Green Inductor Coils Ferrite Ring Toroid - 100pcs

These are obviously pure ferrite. They saturate easily at low frq which is expected. They therefore aren't very good for generating flyback voltages but they are very nice chokes and work well for that purpose. Ymmv may vary depending on your application of course but I have been happy with these. Thank you for a clean toroid that met expectations nicely!

They're all the same size, have strong enamel, and are made of ferrite. Dope.

Seems to work good for RF.

I made a few 'chokes' and transformers with these cores and they worked well. The only bad thing is there are too many! haha

Arrived timely and in tact. Seem to be decent quality though I have not used one yet. Do not appear to have anything wrong with them.

these are SMALL, wire at AWG 14 is not going to wrap more than a few times. I used insulated 23 AWG stands pulled from Cat6e cables and they worked pretty well. The magnetic permeability is somewhere around 2400 from what I tested. If you are looking to make very small uH inductors one warp of wire on these will be excessive. IF I had any real complaint it would be the lack of advertised magnetic permeability. Had several broken in the package, if your postal workers are rough it might be a problem.

I used several to make and experiment with a "joule thief" circuit. They worked perfectly.

Ordering these was the best mistake I ever made.