1. Reliable accuracy and durability.2. Automatic power off when no signal.3. Small and light weight, convenient to carry.4. Low voltage indicator, Real-time spot-checks.5. Widely used in hospital, home health care, oxygen bar, community medic centre, alpine area, sports health care etc. Hands need to be warm to get a proper measurement (basically you need good bloodflow to your fingers). Specifications:Material: ABSColor: BulePower by: 2xAAA Battery (not included) Notes: The battery installed in the device is in two opposite directions. When you install the battery, you need to check the positive and negative signs on the battery slot first, because the wrong polarity will cause the device to not work properly. Package Included:1 x Fingertip Oximeter1 x Instruction Manual1 xPortable Lanyard Notes:1. Manual measuring, please allow 1 ~ 3mm error, thank you.2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. We guarantee the style is the same as shown in the picture. Please contact us with any problems before opening an eBay Case, return or leaving us negative feedback so we can diligently work to solve the problem for you.