Abstract: The present invention relates to powder-layer three-dimensional printers (2) having a discrete supply hopper (340) and a recoater (20). The discrete supply hopper (340) is configured to transfer a build powder to the recoater (20) in a manner that enhances the uniformity of build powder layers that are dispensed from the recoater (20). In some embodiments, at least one of the discrete supply hopper and the powder hopper of the recoater is adapted to selectively contact the other, seal against the other, and/or have one partially inserted inside the other so as to diminish or prevent powder pluming during the transfer of build powder from the discrete supply hopper to the recoater.

Abstract: A first mail carrier includes a stiff flat back portion, an open pouch connected at the bottom of the back portion at a lower half thereof, a stiff flat flap connected at each side of the back portion and a handle connected to each flap. The pouch includes elastic at the top for ensuring that mail carrier contents do not fall out. A second mail carrier includes a sack, a rigid member connected to the top of the sack for holding the sack open and for retaining the shape thereof, a strap connected to the sack that may include a quick attach/release mechanism and/or a strap adjuster, and a cover flap for the sack. The mail carriers may be used together as a mail carrier system for carrying different sized mail.