Bidding box for home-played games. Use of bidding boxes has several advantages over oral bidding: it reduces noise in the room, prevents bidding being overheard at neighboring tables, allows easier review of the auction, and reduces the opportunity to pass unauthorized information to one's partner (intentionally or not) by the manner and intonation in which one makes one's bid. A bidding box is typically a plastic box with two slots, each containing a set of bidding cards. One slot contains 35 cards with symbols of bids (5 denominations—clubs (), diamonds (), hearts (), spades (), and notrump (NT)—in seven levels of bidding,
Philatelic auction view the items beforehand, either in a catalogue, in the auction house, or both. Philatelic auction A philatelic auction, or stamp auction is a sale of stamps, covers and other philatelic material usually run by stamp dealers or specialist collectibles auctioneers, such as, David Feldman, Christie's and Sotheby's, where prospective purchasers place bids in an attempt to obtain the desired items. The highest bidder for each lot (described item or items) makes the purchase. Auctions are generally divided into mail sales, where bids are accepted by mail, and public sales, where mail bids are combined with live bidding from individuals