There's also a new 500GB budget variant for less demanding users on March 3, 2021, 7:18 In brief: Originally launched in 1TB and 2TB capacities, Crucial's compact and durable X6 portable SSD lineup has been expanded at both ends with a wallet-friendly $69.95 500GB model and a capacious $489.95 4TB model. Crucial's new 4TB variant of the mid-range X6 portable SSD gets a slight boost in sequential read speeds over its lesser storage siblings (800MB/s vs. 540MB/s), though it's still trumped in terms of performance by Crucial's own high-end X8 series and Samsung's best-in-class T7 Touch that can reach an impressive 1,080MB/s.