A shopping bag helped cops nail a Brooklyn jewelry-store thief, police said.

Joseph Neal, 31, and another man allegedly took nine bracelets worth $11,000 from the Williamsburg store on Graham Avenue at 12:58 p.m. on July 20.

A camera captured the accomplice holding a bag bearing a Sprint logo, sources said. So cops went to the nearest Sprint cellphone store, where a worker identified Neal, the sources said.

The warrant squad busted him Thursday. The other man is still being sought.