idont know, but if theyre custom, then its interesting that those sticks have lead tape at the 3 and 9 positions. you can see this more clearly (although its visible in the last pic above) in a picture of him in the new tennis magazine
I own the LM Radical OS... and watched him play yesterday... and did wonder why the racket looked smaller than my 107"... looked more like a 100" to me, but I guess it could be 104".