Hoya 49mm HD Nano II UV Filter 

HOYA's HD NANO Mk II series is devoted to professional photographers and is designed to resist severe shooting conditions and accidental physical damages.

Besides chemically hardened optical glass, the series adopts a newly developed ultra hard scratch resistant nano coating which provides not only reliable protection of the camera lens, but also protection of the filter itself.

• 32 layer (both sides) ultra-smooth, ultra-hard nano coating
• Stain resistant, water & oil repellent coating makes everyday maintenance easier
• Ultra-hard surface coating is 800% more scratch resistant than general coating
• High Density Sharp Cut UV glass
• Chemically Enhanced Optical Glass is 4x Stronger than usual optical glass
• Very Thin Frame, Front thread to attach lens caps and other filters
• Press mount technology holds glass securely
• Made in Japan

The UV (UltraViolet) filter absorbs the ultraviolet rays which are invisible to human eyes, but can make areas of outdoor photographs hazy and indistinct.

This multi-purpose filter can also serve as a permanent lens protector and while designed specifically for high-resolution digital cameras, the UV filter can also be used on film cameras.