Abstract: A cartridge type pressure switch is formed with a cup-shaped contact flanged outwardly at its rim and slidably nested in an annular spacer. A flexible diaphragm has an integrally formed annular bead ring which is stretched over the spacer to secure the diaphragm in place over the cup-shaped contact. A spring nested in the cup-shaped contact has the outer end registered against a deck or spring retainer. A pair of stationary contacts on opposite sides of the spacer have terminal portions extending outwardly through the deck. The spring biases the cup-shaped contact in a direction to seat the flange against the stationary contacts. When the cartridge is inserted in a bore, the bead ring is compressed to seal the cartridge in the bore.