Great Replacement for Sonicare Toothbrush, with a Little Work
I have an older Sonicare toothbrush from Costco.  I wasn't able to find the exact model name of it.  These batteries appeared to be the right size and layout for my toothbrush, so I gave it a try.  Similar to another reviewer, I had a hard time getting all of the solder out of the holes to make room for the new battery.  I spent a bit of time with a soldering iron, a desoldering braid, and finally some spare copper wire.  Using the copper wire, I was able to get the holes cleared of old solder and make room for the new batteries.  Then I was able to re-solder the new battery without running wires around the outside like the previous reviewer did.<br /><br />Results:<br />Before the replacement, I had to charge my toothbrush every single day.  Sometimes it would not even last through 2 brushings.  With the new battery, I went a full week before the orange charge light came on.  And it went another week before I really needed to charge it.  So I'm now getting 1-2 weeks of battery life on these new batteries.  I have been using them for about 2.5 months now, without any issues.  I would highly recommend them, as long as you're not afraid of a soldering iron.
Rating: 5 stars