The Harken 170 3.00in Hexa-Cat base block with swivel and cam cleat uses Hexaratchet® holding power to grip loaded sheets while allowing quick, controlled easing and trimming. A switch on the side engages and disengages the ratchet mechanism. Combine the 193 and 170 Hexa-Cat bases with Big Bullet or 2.25 in (57 mm) blocks for purchases from 5:1 to 8:1.