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In comparison to devices relying on components that operate only briefly and do not normally conduct electricity ( such as MOVs or GDTs ), SM devices tend to be bulkier and heavier than those simpler spike shunting components.

The initial costs of SM filters are higher, typically and up, but a long service life can be expected if they are used properly.

In-field installation costs can be higher, since SM devices are installed in series with the power feed, requiring the feed to be cut and reconnected.