We currently use a mix of Renata (Swiss made by Swatch group) and Seizaiken (Japanese made by Seiko) silver oxide and Maxell lithium cells. Our silver oxide stock is being moved towards Seizaiken because of potential supply problems on the horizon with Swatch group. These brands are used exclusively because, over nearly 20 years, we've found that their reliability - especially in leak resistance - is unsurpassed.
All battery changes include a replacement back seal if required by visual inspection, and pressure testing is available if required for water resistant watches to guarantee continued resistance. For personal visitors both can be done "while you wait", for postal customers return is normally within 24 hours of receipt. Unlike many repairers we don't charge extra for the same battery just because of the name on the dial!
If special seals (eg: replacement crowns) are required to reinstate water resistance then we quote at the time and there's no charge if you decide not to proceed. In that instance we even return postal jobs at our expense!