PH PandaHall 540pcs 6 Colors Brass Wire Guardian, Wire Guard Thread Protector Cable Protector U Shape Thread Protector Loop Guardian Terminator for Bracelets Necklaces Jewelry Making, Golden/Silver

I don't think the brand necessarily matters, but these came from a kit like this and look similar to these https://a.co/d/0dMl9x9b. I think any brand of wire guards will do though - as long as they hold up from a good tug :)