Hello, Just asked for a couple of racquets from TWE's demo program. Received the racquets today, nice state, maybe a slight scratch on the head of one of these if you have bionic eyes. I'm just curious about the string used on these racquets. It's a black string. When pulled it snaps back, which means that it's likely a monofilament co-polyester. All writings are unreadable. Can I have more information on it, and if possible the range of tension? More or less unrelated to this, am I allowed to change the overgrip of a racquet if it gets used? I automatically added one on the Wilson Blade BLX (gold/black), because as the TWUSA review mentioned, it felt slippery. I did not use the small part that is supposed to be stuck onto the grip so it wouldn't make the grip sticky though. The other racquet is a Babolat Pure Storm Ltd. (+), which comes with a leather grip and was sent with an overgrip on it in order to protect the grip. Thanks in advance.