Opteka 500mm f/8 High Definition Telephoto Mirror Lens for Pentax K-1, K-3 II, KP, K-70, K-S2, K-S1, K-500, K-50, K-30, K-7, K-5, K-3, K20D, K100D and K10D Digital SLR Cameras High definition optics produce sharper, more intense pictures Incredibly compact and lightweight, Fully Multi-coated, Manual Focus Soft pouch and three (3) rear mounted, 30.5mm filters, (ND-2X, ND-4X & Skylight) May be combined with the Opteka 2X Multiplier for 1000mm Zoom (Sold separately - 47st Photo Item Code: B000JSZ41S) 10 Year Warranty