With 4 TB of storage, this is a good HDD drive if you need a larger storage unit. This model's rotation speed is 5 400 rpm.
From Amazon
Transcend 4 TB Rugged Portable Hard Drive - Shock Resistant USB 3.1 Gen 1 StoreJet Navy Blue - TS4TSJ25H3B
Clove Technology
Transcend StoreJet 25H3 external hard drive 4TB
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