A security apparatus for securely displaying a portable electronic device comprises a base, a holder and a securing portion. The base defines a central bore and comprises a holder engagement portion. The holder comprises an outer surface defining a plurality of vertical channels terminating in a support surface forming a support platform. A holder groove is defined between the support platform and the outer surface of the holder. The securing portion comprises a plurality of projections coupled to each other by one or more lateral braces. Each of the plurality of projections comprises a lateral extension that is configured to contact the support surface and engage a holder groove. Rotation of the securing portion relative to the holder moves each lateral extension of the plurality of projections into the holder channel and secures the securing portion to the holder.