Copper Cathodes needed, 5.000 MT month for 12 months

Please quote COPPER CATHODES, square sheets, 24 "x24" x5/8 "at 99.76% purity. For industrial applications, at level of 5.000 MT month for 12 months, for a total of 60.000MT.
Quotations have to include the cost of the cathodes, ocean freight, insurance and certificadte of SGS:
As copper price is volatile lately, it will be interesting if you consider in the quotation the possible variability of the price.
Please take into account the signing of the supply contract 90.000MT, if variable (quality, price) allow it.