Features: End points of nurse calipers are adjustable to the desired length to meet various needs, providing you with a good experience. The EKG measurement tools come with various functions, they are practical for electrocardiogram drafting, nice supplies for schools and nurses. Reliable material and strong structure make the caliper measuring tools are not easy to deform or corrode, and can be applied for a long time. Specifications: Material: 304 stainless steel and plastic Main color: black (EKG caliper) Size: about 1 11/16 x 6 3/8 inches (EKG ruler) Package includes: 2 x EKG calipers 2 x EKG rulers Notes: Manual measurement, please allow slight errors on size. The color may exist slight difference due to different screen displays. Pointed parts included, please keep away from children.