Danny Briggs also signs on having originally been part of Welsh Fire's squad in 2020
David Warner have re-joined Southern Brave for the first season of The Hundred.
The Australia all-format opener was the third pick of the pre-tournament player draft.
Warner was lined up to play for Brave in last season's inaugural edition.
The T20 Blast's all-time leading wicket-taker Danny Briggs completes the Ageas Bowl-based team.
Left-arm spinner Briggs had been part of Welsh Fire's squad for the 2020 tournament prior to it being postponed.
The pair join a squad that already boasts England internationals Jofra Archer, Liam Dawson, Chris Jordan, James Vince and Craig Overton, as well as overseas stars Andre Russell and fellow-countryman Marcus Stoinis.
The Hundred - men fixtures 2021
The Hundred - women fixtures 2021
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