Abstract: A retention device for portable audio, video, and power adapters commonly used with portable electronic devices (e.g., mobile phones) includes a shell that is configured to receive a removable insert formed from a resiliently deformable material, which retains and protects an adapter for a portable electronic device. The removable insert may be interchangeable with a plurality of inserts, each of which comprises a cutout region configured to accommodate and retain a corresponding adapter.