Abstract: A device for transporting and buffering a flow of small articles, such as mail pieces, includes a conveyor belt that moves the articles onto a linearly displaceable carriage which delivers the articles into a buffer stack at a constant entrance angle regardless of buffer stack size. Articles in the buffer stack are supported and agitated by a plurality of rotating beater bars. Agitation causes skewed articles to level while the rotation of the beater bars transports the articles toward a moving edging belt that propels them into a feeder output. One of the plurality of beater bars includes screw thread sections for advancing the articles toward the feeder output.