| 摘要 |
A portable postal scale for determining whether the weight of a letter exceeds the maximum for a given amount of postage, for example, one ounce. The scale comprises an elongated beam having a letter holding means, a fulcrum and a preloaded portion. The letter holding means comprises two upward facing arms forming a narrow opening or slot for holding the letter to be weighed in an upright position. The part of the beam from the fulcrum to the end opposite the letter holding means is the preloaded portion; the preloaded portion has sufficient weight to balance the beam when a letter of predetermined weight is placed in the slot. A calibration means for the beam and longitudinally located recesses made suitable to accept a movable counterweight for determining additional increments of weight are provided in other embodiments.
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