A conveyor system with an endless loop tubular system has an inlet provided for permitting material to be introduced into the tubular system. An endless loop flexible member extends through the tubular system and has inserts disposed thereon for moving material along the endless loop tubular system. A drive mechanism is provided for causing the endless loop flexible member and inserts to move in at least one direction through the endless loop tubular system. A novel outlet valve disposed in the endless loop tubular system is provided for selectively permitting the material to fall out of the endless loop tubular system by gravity, the outlet valve having an opening with an insert entry end and a insert exit end, a first side and a second side and wherein the insert entry end is larger than the insert exit end.