Airgoesin Pen Style ECG EKG Caliper Ruler Precision Drafting Divider 1 pc BK Brand Airgoesin Material Silver, Steel, Brass. Item Dimensions 9.9L x 0.8W cm Range 1.6E+2 millimeters Measurement Accuracy +/-0.00012 inches About this item ECG EKG caliper for measuring ECG wave sections. High quality. Adjustable screw to loosen and tighten the arms. Chrome-plated brass arms feel heavier than other materials (stability). Hardened steel points. Comes with a luxurious silver case. Product Description ECG EKG caliper for measuring ECG wave sections. High quality. Adjustable screw to loosen and tighten the arms. Chrome-plated brass arms feel heavier than other materials (stability). Hardened steel points. Can be attached to a uniform with a clip for easy carrying. Length: 95mm (from caliper top to point), 160mm (cover is on caliper). Comes with a luxurious silver case.