Abstract: An eyeglass frame supports a pair of mounting adapters. Each mounting adapter includes a connecting mechanism for removably connecting an optical device. The connecting mechanism permits the optical device to be inserted with a low insertion force, but requires a relatively large force for removing the optical device. The connecting mechanism includes an interior bore that accepts an insertion shank on the optical device. A series of Teflon balls are placed in radial channels in an outer wall of the mounting adapter. An O-ring in a groove in the outer wall urges the Teflon balls into the radial channels. The radial channels are shaped to prevent the Teflon balls from falling into the insertion bore, but allow the Teflon balls to protrude partly into the insertion bore. The insertion shank of the optical device has a bevel that forces the Teflon balls out of its path as it is inserted into the interior bore.