•Button/coin cells: All 1.5V/3V types (CR2032, CR2016 etc. — ideal for scales, car keys, watches). ???? ANENG BT189 Universal Battery Tester | LCD Volt Checker for AA/AAA/C/D/9V/Li-ion/Button Cells. •9V block batteries: 6F22 (essential for smoke alarms, wireless doorbells).
