The England and Wales Cricket Board (ECB) has announced its plans for the new domestic competition starting in 2020 to use an innovative 100-ball format.
Leagues for men and women will feature the same format, brands and identities across the competition, with the ECB outlining key aims to attract a wider audience and differentiate from other formats.
It states the proposal was presented to first-class counties' chairmen and chief executives at Lord's, receiving "overwhelming support".
"This is a fresh and exciting idea which will appeal to a younger audience and attract new fans to the game," said CEO Tom Harrison.
"Throughout its development, we have shown leadership, provided challenge and followed a process. We will continue to do that as the concept evolves.
"Our game has a history of innovation and we have a duty to look for future growth for the health and sustainability of the whole game."
