√ Smooth indentation in the middle makes opening, closing easier. Accurate Measurement: Protective plastic cover includes a ruler for easy measurement reference. Premium Quality EKG Caliper: Measuring tool made with high quality brass materials for measuring electrocardiogram wave sections., EKG Calipers Length: 11., 5cm/4., 5inches (from top to points). Normal ECG Electrocardiogram P Wave , PR Segment , PR Interval , QRS Complex , QT Interval St Segment T Wave U Wave The HNBun EKG ECG Caliper is a precise electrocardiogram divider designed for healthcare professionals. This durable measuring tool, crafted from high-quality brass, provides accurate measurements for electrocardiogram wave sections, making it an essential item for nursing and medical use √ Brass arms feels stronger than other materials., √ Protective plastic cover, 9., 7 cm/3., 8inches molded ruler for measurement reference. √ Brass arms for accurate measurement of tracing intervals. Super accurate and stay steady. Feature: √ EKG ECG Caliper Made of high quality brass material, sturdy and durable. Easy to Clip: Protective cover with a plastic clip that is easy to attach to a nursing uniform. Electrocardiogram ECG Ruler Cardiogram Transparent Soft Heart Rate... Lightweight and durable, easy to carry around. Buy Melleco ECG EKG Calipers Pen Ruler Measuring Precision Tool For Cardiologist With Case Ecg Caliper