Instruct: Classify Amazon reviews into positive or negative sentiment
Query: battery for canon sd400

Though the spec syas that this works for an SD400 camera, it does not! We have charged it completely, and have tried it but it seems the contacts are smaller or something and therefore does not work! We have tried this several times thinking that this may be our mistake, but to no avail. Has anyone else used this for SD400 ? When I compare this battery to the original one I got with the camera, the metal contacts seem smaller - maybe that's the problem.