The Magnetron is an OEM part for LG microwaves. As the primary cooking mechanism, it generates microwave energy to heat and cook foods quickly. Causes can be from normal wear and tear over years of use. Damage may also occur if the microwave interior is exposed to moisture, spills or debris. Symptoms of a faulty magnetron include: Slow or ineffective cooking Hot or cold spots in cooked foods Buzzing or humming noises emanating from inside the microwave This OEM LG part is also compatible with some Kenmore models.2B71165R (AP4437489) replaces 1156691, AH3517729, EA3517729, PS3517729.