Cashmans Two-Way Gate Latches are a must for every farm.  It only takes one hand to open and close this latch.  With a self closing slam latch feature, you will no longer struggle with carrying things through the gate while trying to keep animals in and closing the gate at the same time.  When the gate is in the closed position, the weight of the gate rests on the latch rather than pulling on the opposite post.  This will eliminate hard to lift sagging gates.