Payment: by 100% irrevocable L/C at sight opened 求翻译

问题描述:

Payment: by 100% irrevocable L/C at sight opened 求翻译
Payment: by 100% irrevocable L/C at sight opened by a 1 st class bank agreeable by the Seller that must be opened 15 days prior to the 1 st date of laycan for each shipment. 我英语水平半桶水,不是很看得懂,求大神翻译.

付款:由卖方同意的一流银行,在每批装船装期的头一天的15天前,开出100%金额的不可撤销即期信用证.