The 40.5mm Lens Hood is designed specifically for the Q-mount series of lenses. It fits the PENTAX 01 Standard Prime and Pentax 02 Standard Zoom lenses for the PENTAX Q-series of Interchangeable Lens cameras. The compact bayonet-shape hood shades the lens from stray light and protects it from dust, moisture and the inevitable bump. The hood screws onto the filter threads and clicks in place using the locking ring. It is made of black, hard plastic and is an important accessory for smart photography.