Watch: Usher & Nas perform ‘Chains’ at TIDAL X charity concert...

For the very first time, Usher and rapper Nas performed their anti-police brutality anthem 'Chains' last night, during the TIDAL X: 1020 charity concert.
In paying his respects to police brutality victims Trayvon Martin and Eric Garner, the R&B crooner came out in handcuffs and then broke free. Such powerful stuff. 

The liberating performance was broadcast on 'Jimmy Kimmel Live,' and took place at Brooklyn’s Barclays Center. 

Check it out inside.