not all microwaves come with a filter. The presence of a filter in a microwave oven depends on its design and intended purpose.
Some microwave ovens have built-in filters to help reduce the amount of electromagnetic interference (EMI) they produce. These filters are designed to prevent microwave radiation from leaking out of the oven and interfering with other electronic devices nearby. This type of filter is commonly found in modern microwave ovens to comply with safety regulations and standards.
However, not all microwaves, especially older or more basic models, may have EMI filters. The absence of a filter doesn't necessarily make these microwaves unsafe, but newer models with filters are designed with additional safety features in mind.
If you're concerned about the safety and functionality of your microwave oven, it's best to refer to the user manual or contact the manufacturer directly to inquire about its specific features, including the presence of any filters. Always follow the manufacturer's guidelines for proper usage and maintenance of your microwave.