This drain outlet for the flangless WaterGuard Basement Drainage Channel (aka BaseDrain).
A pipe, approximately 1ft long, is included to connect to the sump pit. If you heed to extend the pipe you can sleeve over it with yourown 3" pipe, you do not have to make a waterproof seal or joint.
Our FloodBuster sump pit was designed to be compatible with this outlet and has special cut out ports in the side for the pipe to go through.