it's a radar like thingy but not decoration.
it can let me having 100% of the combat efficiency during night battle.tar-chan, what's the use of those bunny ears looking decoration?then it still a decoration... why you have to be mad.rubrub
huh!
rub your face!wearing it give me a high tech looking can't i?also you ain't night battle specialist anymorebut you didn't have it when you dressing as bunny girl on the field isn't it?wearing because it's cute