So is the adjuster part of the brake lever or is it a separate adjuster?
The in-line adjusters are basically a hollow bolt with a cable stop on one end, and a nut with a cable stop on the other end. The cable housing is split and the ends are seated in the cable stops on the 'bolt' and on the 'nut', and turning the 'nut' in relation to the 'bolt' makes the split in the cable housing wider or narrower. Pulling the two ends further apart has the effect of 'tightening' the cable, turning so the two ends are closer together 'loosens' the cable.