ECG caliper: you receive a black EKG caliper with protective cover, which is suitable for ECG mapping, which is a choice for schools and hospitals High-quality material: The ECG caliper measuring tool is made of high-quality material, reliable and not easy to bend or deform, providing you with long-term service With scale: there is a scale design on the protective cover, which is used for measuring reference. The measuring range is 0-6cm/0-2.4 inches, bringing convenient use experience Easy to use: These calipers can be adjusted to the required length to meet needs. The compact appearance can be stored and carried anywhere you like Wide application: Our EKG calipers are very suitable for nurses, students and doctors, and can be used to measure correct results and data to meet your daily measurement needs color:Black Material:Metal Package Contents: 3 x EKG Caliper Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.