A jockstrap (or similar)

An item of removable bedding that sits on top of or encases a mattress to protect it from stains and sometimes to protect the sleeper from allergens and irritants.

An appliance designed to protect electrical devices from voltage spikes by limiting the voltage supplied to an electric device by either blocking or by shorting to ground any unwanted voltages above a safe threshold.

plural of earthquake protector

(earthquake engineering) A sliding type of low friction base isolation for protection of building structures against lateral impact of strong earthquakes.

A sheath, usually of plastic, designed to fit in a shirt pocket and hold pens and other small implements, preventing them from tearing or staining the shirt.

plural of pocket protector

plural of Hector protector

(cricket, slang) A hard protector for the genitals worn inside the underpants by a batsman or close fielder; a box.

plural of sheet protector