This also works for BT405 hope this helps

Excellent tutorial I didn't buy a battery off amazon tho I used an ikea ni-mh AAA rechargeable battery instead works like a dream again thank you

The end cap can also be easily levered out with the charging bracket

You should put the brush in hot water for 5 minutes, so that the plastic becomes soft and you don't break the snap so easily.

With the (almost?) Identical Oral-B Pro 2500 model, there is a small opening in the hard plastic shell on the front about 5mm below the lowest signal light, over which only the rubber coating runs (i.e. only palpable, not visible from the outside). You can push the front catch inwards through the rubber.

The battery is not soldered it is spot welded