Kitty String is high quality yoyo string. Kitty "Fat" is a soft and thick string with 12 strands of thread made from 100% polyester fiber. This is specialized yoyo string, good for whip and slack tricks. Many players use this also for a wide gap non-responsive yoyo to give it a more responsive feel and a tighter bind.
Pre-tied yoyo strings, each approximately 43-45 inches in length. Individual strings are knotted on the end, you will need to tie a simple loop for finger attachment and adjust the length. Stretch your Kitty String before using it, this helps reduce the elasticity and twist while playing.
Your individual preferences may vary, but as a general guideline polyester yoyo strings are excellent for high-performance ball-bearing yoyos. Soft to the touch, 100% Polyester strings gives smooth spinning performance for intermediate/advanced players when using non-responsive yoyos.