The present invention provides a blade clamp for an electrically powered reciprocating saw. The cryptographic modules are capable of implementing the USPS Information Based Indicia Program Postal Security Device Performance Criteria and other required VBI standards. The transferring apparatus is contrived to move among the shelves and transfer cassettes C between any shelf and the transfer port. A layer of metal is deposited on the second surface of the semiconductor substrate and forms an ohmic contact at the interface of the metal and the zone of increased carrier concentration. In an embodiment, the thermally activated viscosification compound includes at least one water-soluble hydrophobically modified polymer comprising a hydrophobic substituent having from about 1 to about 22 carbon atoms. When there is a remaining mail item deviated from the nip of the switchback roller and remaining in the switchback unit, a pressure roller is pressed to an output roller always rotating in the direction of R1, the remaining mail item is held and fed out to the nip.