You know Bill that's what we all thought at first looking at Brent wheel, the center section looked like a shiny rotor, you couldn't see the bolts from the outside, it wasn't till you looked up closely did realize that wasn't a rotor. The cap is Alum, and the knockoff said Halibrand, in fact they are vintage Halibrand knockoff's, they even have a part# stamped on them. Brent brought an extra set (Knockoffs) off Ebay, and they came from a vintage sprint car. If Brent gets on here, he can explain much better then I, he did his homework on these. Anything is possible correct Bill
Cheers Tom. P.S. I think you're right Bill, I just looked on my 32" screen, and Yes I believe I see a caliper.