An improved flagship model with overwhelmingly strengthened scratch resistance performance Wide spectral flatness throughout the visual as well as infrared light region to maintain color fidelity 4x-Filter factor, 2-stops, 0.6-Optical density, ascertained color fidelity The most outstanding maintenance performance in harsh environments, Dust-/Water-/Oil-/Fingerprint-resistant Easy handling by protective edge-sealing High affordability despite the same optical quality compared to the first generation WSND. Made in Japan