Felt TKR4 wheel question.

[Pointy boy]

Hi, trying to get a straight answer to a simple question. Google has been worse than useless, so I’m hoping someone here has actual knowledge! Are Felt TKR4 wheels (as fitted to my 2015 TK3 track bike) rim brake compatible? They appear to have some sort of braking surface, but it’s really not clear.
If anyone knows for sure, I’d appreciate it. Thank you!

 

[fossyant]

Is it a machined braking surface or black - if black they probably won't stop as well.

These 30mm rims are often Kinlin rims under a different badge - pretty sure my Mavic Cosmics are the same rims as Miche 30mm rims.