The is an unopened C&H Precision GL-RSH V4 MIL/LEO Optics Mounting adapter is designed for 4th and 5th gen Glock MOS models G17, G17L G19, G22, G23, G34, G35, G40, G41, G45, and G47.

This adapter can house
Holosun: 407C, 507C, and 508T
Trijicon : RMR, RMR HD
Olight: Osight, Olight X
Viridian: RFX35