I bought this Professional Care 5000 TwinPack to replace a single Braun electric toothbrush that was getting old and failing to hold much battery charge. The new twin set works great, and these brushes do a good job. There is one downside - despite having the same model number as the unit I replaced (Type 4729), these new toothbrushes have a single-colour LED charging light that only glows orange during charging - it doesn't change colour when the unit is fully charged. The old brush had a 2-colour LED that indicated when it was fully charged. This is actually quite annoying, especially since a) it has the same model number and b) a full charge cycle takes 12 hours. Hence I deducted one star from an otherwise good product.