Maxell Watch Battery 348 / SR421SW by Maxell Sale $2.49 | / SKU BT-SR421SW 1 2 3 4 5 6 7 8 9 10+ Quantity Chevron down icon Quantity Add to cart Spinner icon Notify me when back in stock Email address Email me when available Maxell Watch Battery SR421SW a 348 battery, silver oxide, low drain 1.55 volt, diameter 4.80 mm, height 2.15 mm.