I have used several Brother label makers, all of which use the TZ series tapes.  Of those tapes, my two favorite are black on white in this width and the 3/8" width.  I prefer the 1/2" width for hanging file folders because the label fits nicely on the tab.  I like the 3/8" width (TZ-221) for use with manila folders because the narrower width positions closer to the edge of the tab.