Adjuster thing for rear Derailleur

[RyanW]

Im trying to find the name of what i am after, so i can try and find a new one. Im after the "bit" that connects to the rear cable guide and allows you to make micro adjustments.

Picture attached.

What is it called?

 

[Sittingduck]

Barrel adjuster

 

[gbb]

Make sure you get a 5mm GEAR adjuster, not a 6mm BRAKE adjuster. I got one from Ribble, they're only a few quid each.