题目内容：
Letter of credit can be worded SO that payment is made on the very date that the shipping documents are received by the confirming bank，or，if you wish to give the buyer extra time，an L/C can also be worded SO that payment is made 30，60，or up t0 1 80 days，which is the customary maximum．It is vitally important，though，that the wording in the L/C be clear and specific and equally important that the words in the shipping documents conform precisely with the wording of the L/C．Even slight variations can cause delays in payment until the questions are clarified and answered．Letter of credit can be extremely flexible．An unlimited number of provisions can be specified．For example，the buyer can even indicate what types’ of marking should be appear on the shipping containers．
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