L/C方面的问题求助，急救！SOS

今天接到一单，灰常鸡冻，但是客户要求30% tt .70 % lc. 之前没接触过lc。求助于外贸老鸟们。万分感激，内容如下： our payment for you will be letter of credit (l/c) through dubai islamic bank. first we will open the l/c in your name and we will instruct our bank to give 30% advance payment and the balance 70%you will get??once you ship the compressors and submit all the original documents as per the l/c requirement to your bank, your bank will send all the documents to our bank. when our bank get all the original documents??they will transfer balance 70%??to your account. if this banking arrangement is acceptable, we need a new??pro forma invoice in the name of dubai islamic bank??in the following address dubai islamic bank account of streamline airconditioning trading llc p.o. box. 120903 dubai, uae