0.75 + actual shipping.  Right now running @ 550mhz for optimum heat/power.  This is the higher chip count model of s7 - qty 162 - thus more efficient than later batches.  The Batch 2 runs 4.6Th @ 575mhz, and Batch 4 runs 4.8TH @ 600mhz.  Also the controllers handle more s7 blades if needed.  Sold only as a pair.  Run completely stock Antminer settings, never had an issue.