It's the babolat vs power from ages ago. I never liked the stuff, even during stringing it would fray. I belive it is old stock, which never got sold because babolat phased it out in favour of the vs team, which is MUCH better. Serena seems to like it, but thats because she gets it for free. I broke a set of the stuff while stringing at this year's US open, my only broken gut job, was on Sargisian's frame i think, or might have been Kutznetsov, they use the same rackets