Her name is Magic or Scarlet's Magic. She a first filial Savannah cat and she is an outstanding cat with massive presence but a gentle domestic cat character. Can't beat it. The measurement is from ground to shoulder (17.1 inches or 43.43 centimeters) and she is a Guinness World Record holder at the date of this post. Here she is:
Magic was born and raised at A1 Savannahs near Ponca City in Oklahoma, USA. Her father was a serval wildcat and her mother a domestic cat, probably a Savannah cat.
Another very tall and impressive F1 Savannah cat is Titan.