US Pat. No. 10,251,290

PROTECTIVE CASE ASSEMBLY FOR HANDHELD DEVICE

EVOLUTIVE LABS CO., LTD.,...

1. A protective case assembly for a handheld device, comprising:a detachable component having a component outer peripheral surface;
a casing body having a casing body rear peripheral edge surface formed with at least one casing body protrusion; and
a coupling unit detachably coupling said detachable component to said casing body, said coupling unit including
at least one first protrusion extending outwardly from said component outer peripheral surface, wherein said at least one first protrusion is annular,
at least one second protrusion extending outwardly from one of said at least one first protrusion and said component outer peripheral surface, said at least one second protrusion cooperating with said at least one first protrusion to define therebetween an engaging groove for engaging with said at least one casing body protrusion; and
at least one main groove formed in said casing body for receiving said at least one second protrusion.