Pressure Treated Fence Post.
 
Mortice: we can Mortice to spec for you in advance. PLEASE NOTE this refers to the height of the Mortice('s), as they are all a standard size (approx 25x63mm)
 
Guidelines: Post Mix 1½ to 2 bags per hole depending on size, post would usually go 600mm or 2' into the ground & think about finishing off with a Post Cap.