Reinventing the wheel(ie bin).

What are the two greatest inventions in the history of mankind? The wheel and the bin, of course! And what do you get if you combine the two? The answer is probably the wheelie bin. But boffins at Tower Hamlets Council have gone even better...

This ragtag contraption features a whopping four bins on one set of wheels!!!! The rear bin even boasts a lock to keep contents safe from the tampering hands of ne'er-do-wells.

But what could those "BB" markings mean? If any readers can shed light on this acronym please write in.