1.5 V. QU2400B12. No alkaline battery. Lasts longer (On average across devices). Check power level instantly. Guaranteed 10 years in storage. Guarantee: If not completely satisfied with this alkaline battery product, call 1-800-551-2355 (9:00 AM-5:00 PM EST). Duracell guarantees these batteries against defects in materials and workmanship. Should any device be damaged due to a battery defect, we will repair or replace it at our option. www.duracell.com. Made in USA of foreign and domestic materials.