Resistance to shock and vibration depends on the mass of the moving parts and on the forces holding the contacts together. The criterion of satisfactory performance is the absence of micro-openings of contacts. The usual ambient operating temperature range covered by the snap switches extends from -55°C to +250°C. Operating limits are defined for each type of snap switch. Within these limits, most of the mechanical and electrical characteristics are preserved. However, for cases of intensive use (e.g. numerous thermal cycles with high electrical load) performance may be reduced.