==Overview==

Their main tactical use is to reveal otherwise hidden troops and allow them to be fired on. The standard range of a handheld scanner is fifty,{{Fn|1}} five hundred,{{Fn|8}} or fifteen hundred metres,{{Fn|9}} although walls more than fifty centimetres thick as well as certain shielding materials are able to block them.{{Fn|1}} Longer-range, bulky, auspexes have, depending on craftmanship, a range of five or ten kilometres and can penetrate walls up to a metre thick.{{Fn|6a}} Ground vehicle-mounted auspexes can have a range of fifty kilometres.{{Fn|6b}} Aircraft-mounted auspexes can have a range of a hundred kilometres.{{Fn|11}}