Mark 8 3.5-25X56mm (35mm) M5B2,FF Tremor3 The Leupold Mark 8 is everything you need to make every second count. You can easily fine-tune your point of impact, while preventing accidental movement, with Auto-Locking Pinch and Turn adjustments. The Mark 8 has a 35mm maintube that produces unparalleled windage and elevation adjustment travel, while the ability to bypass the zero-stop in the BDC dial makes zeroing a breeze.