A NEMA 14–30 30 A 240 V grounded four-wire 3-pole single phase receptacle and plug, used for a household electric clothes dryer. There are two flat-blade live contacts, an L-shaped neutral and a semi-circular ground contact. This provides 240 V for the heating element and 120 V for controls. Center rivet is not an electrical contact. Canadian 25-cent piece, about 24 mm diameter, for approximate scale.
<a href="//commons.wikimedia.org/wiki/User:Wtshymanski" title="User:Wtshymanski">Wtshymanski</a>
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