Look what I just got in the post

Nice.
I've just got one of planet x's cnc ultralight calipers. It seems to have no way of connecting a brake cable. Did they leave a bit out or have I forgotten to order an extra part? I'm guessing I need a screw in barrel bit that fits under the red arm in this picture

There's a barrel part that the cable goes through that fits under the 'hook' looking bit.