Hello, Li!

Sorry about the confusion.  We've switched over from the regular red-black twisted wire to the even thinner magnetic wire in a number of our components.  I try not to mix-and-match them in kits, but I must have sent you some of both (old and new versions) in your kit.  

Don't worry, though.  The new magnetic wire really is coated, not bare wire, and is as safe and effective as the old plastic-coated wire.  If you look closely, you can see it's meant to be that way, not stripped or damaged.  Obviously, you still want to be careful not to pinch it or run it over the tops of studs, just like the other wires, but it's so fine it fits into narrower spaces between bricks.  So far, customers have been happy with it.

I hope that's helped, but please let me know if you have any further questions.

Barb Musch (Brickstuff Shipping Manager)