High-quality ECG calipers: made of high-quality metal materials, used to measure ECG waveforms.Adjustable length: point can be adjusted to the required length as required, which is accurate and stable.Accurate measurement: A ruler is attached to the plastic protective cover for easy measurement reference.Adjustable tightness: adjustable screws are used to loosen and tighten the arm.Easy to carry: The protective cover with plastic clip is easy to fix on the nursing suit.Material:Metalcolour:BluePackage Contents:2 x ECG CalipersOnly the above package content, other products are not included.Note: Light 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.