gimmick
gim-mick
noun
A clever, often superficial, device or idea to attract attention or promote something.
"The free gift was just a marketing gimmick."
Thesaurus
Synonyms: thingumajig, gizmo, whatchamacallit, whatsis, thingummy, widget, dojigger, whatchamacallum, thingamabob, doodad, gubbins, doohickey