Instruct: Classify the given review into positive or negative sentiment.
Query: Think about it for just a minute. These gizmos are absolutely useless.

Think about it for just a minute. These gizmos are absolutely useless.(1) Anything that gets on your toothbrush head was ALREADY in your mouth. Unless you think your houseguests are cleaning their shoe soles with your toothbrush while you aren't looking.(2) You are sitting a wet toothbrush head in this gizmo. Which means it is sitting in a puddle of water that is likely to mold/mildew. So you can put mold/mildew INTO your mouth (that was NOT in your mouth before).(3) The puddle of water is likely to (a) rust out the innards of this gizmo and (b) short-circuit the gizmo's electronics.(4) The American Dental Association says these gizmos have no proven beneficial health benefits[...]Given all that, it seems your money would be better spent betting "Hard 8" at the Craps table in Vegas.