It can accidental damage to the lens and also fingers from accidentally touching the surfaces of the lens When taking photos with backlighting, side lighting, or flashes, it can not imaging light from entering and avoid fog From durability ABS this lens guard effectively blocking unwanted light, the light shielding internal extinction treatments During forward and side light photography, scattered light from the surrounding area can be avoided from entering the lens The HB48 Camera Lens shade is specifically 77mm for 70-200mm 2.8G lens, effectively unwanted light from entering the lens and reducing glares for clearer, more vibranted photos