The Ricoh HA-3 Lens Hood & Adapter is a two-piece set of lens accessories for the S10 24-72mm f/2.5-4.4 VC lens, which is designed for the Ricoh GXR camera system. After you remove the camera's ring cap, the adapter twists & clicks onto the body, bayonet-style.
The adapter allows you to screw in filters that have a 43mm diameter. You can also attach the lens hood to the front of the adapter, whether or not there is a filter attached. The lens hood features a "petal" shape that maximizes the amount of hood coverage for the minimum amount of weight and hood area.
The adapter is required for using Ricoh's DW-6 0.79x wide conversion lens or the TC-1 1.88x teleconversion lens for the S10.