Fangrui Product Details Package Includes: You Receive A Ekg Caliper And 1 Parent Ecg Ruler, Suitable For Electrocardiogram Drawing, Which Is A Nice Supply For School And Hospital Quality Material: Ecg Caliper Is Made Of Quality Stainless Steel Material, And The Ecg Ruler Is Made Of Plastic, Reliable And Strong, Not Easy To Rust Or Deform, You For A Long Time Ruler Design: There Is A Scale Design On The Protective Cover And The Measurement Range Is 0-6cm/0-2.4 Inch. Ekg Ruler Measures . 24cm/9.4inch In Length, For Measurement Reference Portable To Use: Ekg Caliper Measuring Tool Can Adjust To The Desired Length To Meet Your Needs, The Compact Appearance Can Be Stored And Carried Anywhere You Like Wide Application: The Ekg Caliper Measuring Tool Ia Great For Nurses, Students And Doctors, Which Can Be Applied To Measure The Proper Result And Data, A Practical Gift For Them The Ekg Caliper Pen Has A Plastic Clip That Can Be Easily Fixed To The Nursing Uniform, And Small Size Also Can Fit Pockets And Pencil Cases Well, Eas