Yeah what Dozers Dad said , a 1990's T300 range triumph. They had 25 litre tanks all the same with the exception of the Thunderbird, similar capacity but a more rounded shape with less emphasis on the kne moulded section.!!
It's from an early 90's Trident, Speed Triple or (I think) Trophy .... maybe 900 Daytona, too. The badge style and colour would suggest that it most likely IS from a Speed Triple (from memory, the only black Trident of the era had red painted tank panels) but that shouldn't really fetch a premium as it is identical (bar colour) to the Trident and others in the range at the time. Granted the cachet of the name might make it seem more valuable but it's only stuff unique or limited to certain models that is generating a premium. But I would say that, though, as I have a black Speed and would be interested to know how much you want for it? If you want to get an idea of the "going rate" ask Trevor at Sprint Manufacturing, or the people at Triumph-Ant Regards, Adie Oh, wait - Louisville, Kentucky? Hmmmm..... let me think about collection only?
Just be aware that triumph had several different blacks throughout the range over the years which are all slightly different Jet Black Diablo Black Assam Black As fitted to Daytonas, Sprints & Speedies So describing it as one or the other could be an issue especially if it doesn't match .................
Definitely an early type tank, note the fitting point top RH of the tank in this picture for a fuel level warning lamp sensor ( screw in ). Some later tanks had a larger mounting hole for a fuel level sensor to drive a fuel gauge eg later Trophy models ( Bolt in ).
