new ebc rotors, is it defective?

[T4R4TR]

Ordered new ebc sport rotors. The front passenger side has an odd groove on the side. Is this a defective rotor? None of the others have this. Seems like it will be unbalanced.

Ps, sorry for reposting this. Just in a hurry to get a response because it has brought work to a standstill and I need this thing to be driveable.

 

[NJshadow93]

I wouldn't worry about it. Doesn't seem to affect the surface of the rotors at all. If you're getting some sort of vibration then get it replaced, but it should be alright.

 

[Greydog]

Don't think it's defective, I've seen other rotors with that groove. I suspect it used to hold the rotor when the face is machined for slotting or cross-drilling.

Or maybe balancing.