Other World Computing offers this 4-Bay Hardware RAID Thunderbolt 2 Storage Enclosure, model no. 0G033S2TB0GB, for $447.74 with free shipping. That's $49 under our mention from April and the lowest total price we've seen. (It's also $251 under the best deal we could find for a similar enclosure today.) It features two Thunderbolt 2 ports, hardware-managed RAID, LED and audible alarms on device failures, and is hardware configurable to RAID levels 0, 1, 1E, 5, 10, and JBOD. Deal ends July 5.