Features Fintertip type LED viewing screen with PR,SPO2, Bar Graph "All-in-one" integrated finger device Simple operation for immediately, real-time spot-checks. Reliable accuracy and durability. 30 hours continuous use. Low voltage indicator. AAA Alkaline & rechargeable battery is available Automatic power-off design. ________________________________________ Standard Accessory 2 AAA Alkaline batteries Operating manual Hang string