Two Way Mirror

The Two Way Mirror was a Christmas gift from Sirius to Harry when Harry celebrates Christmas with the Order, Weasleys and Hermione at number tweleve, Grimuald Place. This mirror was meant so that Harry and Sirius can communicate without interference. Harry barley uses it, and tried to use it after Sirus was killed but failed and was saddened by this. Later on in the series when Dobby is killed by Bellastrix's knife Harry looks into the Two Way Mirror again to see if Dobby is there, failing again.