The Universal Mount for the Osmo is used to mount an external device such as a microphone or flashlight. It comes with two cold shoe mounts with 1/4" threads which can be positioned on any of the six holes.
Osmo - Rotatable Cold Shoe for Universal Mount
Manfrotto Lumie Art LED Light
Osmo - 1/4" and 3/8" Mounting Adapter for Universal Mount
RODE VideoMicro On-Camera Hypercardioid Microphone
Dimensions: 84 mm x 30 mm x 30 mm
Weight: 50 g