Here are the Facts on Feds stick that were posted by someone who had one of them given to him with a pic of the Racket. It is not a stock 90 size. The head size is larger than a 6.0 85 but smaller than the stock Tour 90/Ncode 90. (held it up next to one of each) I measured the beam width. It is 16.5 mm thick (same as the old china PS85 he used to use makes total sense there). Thinner than the stock tour 90/Ncode 90 which is 17.5mm. Balance is even (has lead under the grommet strip all in the top of the hoop. His grip size is small...feels between 1/4 and 3/8, though the but cap says 3/8. The racquet only weighed in at 357g. Swingweight was in the 350-360 range. Some other observations look v closely at the custom string pattern Feds sweet spot area i.e. where he hits most of the time is slightly higher then the middle and if you notice they have moved the concentrated pattern as all rackets have in the sweet spot area up to his area. Also No of mains and crosses and then take a close look as other people have observed the handle area is like the PS 6.0/85 Original. So basically it is a total custom PS 88 mix with a modern shaped throat area of a Tour90/Ncode90, and ps85 handle. The only thing we don’t no is the internal construction of the racket but as he grew up with the ps85 china id guess its v similar.