Its pretty simple, you need two cylinders for the grapple buckets that have the two independant clamping jaws, 1 cyl, for each jaw, dont confuse this with the 2 cylinder 1 jaw setup, the 1 jaw grapples are limited in the materials they can safely and effectivley handle, a 2 jaw is far superior, Ill give you a good example, imagine having all 4 of your fingers glued together, thats like a 1 jaw grapple works, OR, allow them to work independitly, Thats how a two jaw grapple works,:thumbsup: unless your picking up a suite case, theres a HUGE difference, Eric