Gates hung between the posts can be hung on either a square or round post.  Allow for a 5" space between the gate and the post (on hinge side) so that there is enough room for adjustment when it is necessary.  The commonest pin used for this type of installation is the full threaded with nut and washer on either side of the post (#8800-002).  Do not forget to leave the space at the other end of the gate to accommodate the kind of latch that is being used.

If the gate is hung behind the posts the gate is constructed so it is at least 1" wider than the opening between the posts.  Square posts are recommended.   Pins with square shaft (#8317-022) should be used to prevent pin rotation along with the Adjustable Bottom Fitting, which allows for easy adjustment of the gate height at the latch end.   There are several advantages which include:

1. Allow for 1/8" to1/4" of space between the gate and the post.

2. The gate opens a full 180 degrees so it is completely out of the way when open.  This reduces the chances of injury to animals and catching the gate with equipment when driving through the opening.

3. When dealing with livestock, such as horses there is tendency to push on gates rather than pull them back into the field which reduces the risk of animals escaping.  In the UK this tends to be the norm.