NCC-3801
NCC-3801 was the registry number of a Federation  transport/tug that was in service with Starfleet in the mid-23rd century.

At one time the transport container NCC-4000 was attached to NCC-3801. (; )

External links 
 Forgotten Starships at TrekPlace.com - an article discussing the canon appearance of this class
 
 

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30000