Subwoofer in Tannoy Mercury F1 5.1 set

[Foster1984]

Does anyone know what model of subwoofer is in the Tannoy Mercury F1 5.1 set?
This set is placed as "What HiFi? Sound and Visions" best buy for a mid range set-up.

 

[Dr MC]

It's the TS12 sub. A closed box, 12" driver that's down firing. A friend has just bought the full set and I helped set them up.