Cox, 30, first joined the Southern League side in July last year, signing a deal ahead of the 2022/23 season.
Before then, he started his career with Coventry United, playing for the club since their formation in 2013.
The versatile defender, who is capable of operating at right-back and centre-back, has also had spells at both Stratford Town and Tamworth.
He joins a Yeltz side currently three points clear at the top of the NPL Midlands Division ahead of Saturday’s trip to Corby Town.
On his arrival, manager Martin Sockett said: "We are really pleased to get Coxy on board. He brings to the table everything we are about.
"He is competitive, experienced, tenacious and consistent, and is a great signing for our last 11 games."
Photo credit: Nuneaton Borough
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