Boy, the San Francisco 49ers are doing everything to appease defensive coordinator Robert Saleh.
According to Zack Rosenblatt of The Athletic , the 49ers are signing former New York Jets linebacker Chazz Surratt. This is the second former Jet that the 49ers have brought on today.

Surratt is a former 2021 third-round pick of the Minnesota Vikings. However, he never once appeared in a regular-season game for them on defense.
The Vikings used him exclusively as a special teams player, appearing in nine games in his rookie season. Surratt was waived the next year by the Vikings, and that is when the Jets swooped him up.
Unlike with the Vikings, Surratt saw playing time on defense. It seems Saleh was able to get some use out of him. He didn't see a ton of playing time. In 2022, he was primarily on the practice squad.
In 2023, he saw only nine snaps. His 2024 season was where it all changed, which is coincidentally when Saleh was fired by the Jets.
Surratt's defensive usage was mainly as a run defense, so in base packages. His usage with the 49ers will most likely be special teams, with maybe a chance to compete in the base package.
However, I sincerely doubt he will give rookie Nick Martin or Dee Winters a run for their money. Given that the 49ers signed a punter today, it seems their theme is special teams additions.
So, it is probably safe to assume that Surratt is a special teams signing for the 49ers.