Get a SlimSonic XVR-7070 Electric Toothbrush with two replacement heads and one whitening pen for $34.99 at Groupon Goods, and it ships free. That's the lowest price we can find - we saw this model elsewhere for $139! The brush features 3 settings and up to 31,000 sonic strokes per minute, and it can operate for up to 2 weeks on a single charge. The whitening pen uses 35% carbamide peroxide. Sales tax is charged in some states. Limit 3 per person. Ships in 2 1/2 weeks.