The angled flange has a two-degree angle on the flange enabling the valve to hang down slightly to improve dumping and drainage (see below), while a squared flange allows the valve to sit perpendicular to the tank.
The angled flange has a two-degree angle on the flange enabling the valve to hang down slightly to improve dumping and drainage (see below), while a squared flange allows the valve to sit perpendicular to the tank.