Hub Outlet (Outside Caulk Outlet):  A drain connection, usually on side outlet drains, where plain end of drain pipe is inserted and a seal is made either by caulking or by using a compression gasket.  This type of outlet is the opposite of the inside caulk outlet.



Inside Caulk Outlet:  Open bottom type drain connection which is placed over plain end of drain pipe.  The seal is then made by caulking or with a compression gasket.  This type of outlet is the opposite of the hub outlet.



Spigot Outlet (No Hub Outlet):  Male, pipe size, plain end connection for caulking into a soil pipe hub or joining to plain end pipe with a mechanical coupling.



Threaded Outlet (Tapped Outlet):  Internally threaded drain connection for joining drain to a threaded pipe drain line with American Standard & Taper pipe threads (NPT).