A nozzle for a medium or high voltage gas switching device of the type having at least a couple of separable arc contacts (1, 2), comprising a hollow shaped body (100) suitable to be positioned inside the device around the zone (20) where electric arcs form between said arc contacts (1, 2) during switching operations, characterized in that said hollow shaped body (100) has a first portion (101) electrically conductive and a second portion (102) made of electrically insulating material which surrounds at least partially said first portion (101).