Activating it with the Use command (t) will let you see the statistic bonuses of equipment on the current character - same effect as the Mirror skill but without the 30sp requirement. The objet is reusable. The main use is to determine exactly how much of each stat an item gives as a bonus, rather than inexact method counting the "#"s when examining an item (since each except for the last "#" can mean from 1 to 5). To use it on an ally, you have to ride it, then use the objet.