LUID 67mm ND1000 MC Filter Schott B270 Glass Brass Frame ND 3.0 Multi-Coated 67 Luzid Brass Frame. Double Threaded 16 Layer under & over Multi-coating Hardened, Easy Clean Top Coat Water, Oil, Dust, Fingerprint & Scratch Resistant Schott B270 Superwhite Glass Lifetime Warranty