Cat. 2 tractor link triangle for mounting in top link and lower link Price: 95$ Category: misc lifetime: 5$ You can attach your implements with K50 couplings to your tractor with the Cat 2 agricultural rail triangle. The triangle has both a ball head pin and a trailer coupling jaw. This rare combination makes the agricultural rail triangle very versatile. To protect the trailer coupling, the agricultural rail triangle is torsion-proof, as the ball head is always in an optimum position in relation to the trailer coupling. It is attached to both the lower links and the upper link.