Chest leads are made of rubber, foam or fabric materials and are placed on the body. These adhesives are connected to the output wires from the device that produces electric impulses and transmit the electric current to the body. Chest leads are used to perform electrocardiography (ECG) and cardiac exercise testing (CPX). Conductive gel is also supplied with this electrode glue. This conductive gel is spread on the electrodes and then they are placed on the skin. This work allows better control of the voltage flow. The foam layer, like chest lead, is impermeable to liquids in surgical procedures. Chest electrodes are usually 55 mm round, oval or square, and they are made of PVC and latex-free. They are without sensitivity and skin irritation and it should be noted that their use has a time limit.