Brother P-touch 550 - Manual (Page 122)

118
You can choose to align the text in one of four ways.
The default setting is LEFT; however, three other settings are also available.
LEFT
CENTER
RIGHT
JUSTIFY
+
The H.ALI (horizontal alignment) function can only be applied to the entire text; it
cannot be applied to just part of the text.
If the label length for text containing multiple blocks has been set with the LENGTH
function and its horizontal alignment has been set to JUSTIFY, the spaces between
the blocks are adjusted so that the text spreads out evenly along the label.