The Master Circular Polariser is a premium glass filter that helps to eliminate reflections and glare. It features premium Schott optical glass, an aluminum filter ring, and a super slim 4.5mm effective profile. The anti-reflective matte finish ensures that you'll get the maximum amount of light transmission in all conditions, while the knurled edges ensure your lens stays safe when you're on the move. Product Features in Detail Master Circular Polariser Digital HD 72mm FilterIncrease color saturation and reduce reflections. The neutral gray HD polarizing material guarantees excellent images while minimizing loss of light. Constructed with premium Schott optical glass these filters are designed to yield extreme image sharpness. They also feature a precision machined, super slim aluminum frame with anti-reflective matte finish and knurled edges.