When the heart's system misses a signal, the pacemaker sends a signal to replace it. The generator makes the electrical signals when they're needed. It's a smooth, lightweight case containing a tiny computer and a battery. You won't feel the electricity coming out of the generator. The connector is the part of the generator where the lead or leads are attached.
Leads are wires covered by soft, flexible plastic.
They help the generator listen to the heart and carry the generator's signals to the heart. A pacemaker may have one or two leads. The leads won't cut or poke you, and they won't stop the blood from flowing through your vein. Your doctor will choose the type of pacemaker that's best for you. A pacemaker with one lead is called a single-chamber pacemaker.