Transport for London – the organisation that runs London’s metro subway system – has commissioned a set of posters featuring a lever hoist.

The organisation used one of its “preferred suppliers” of advertisements, the media agency Creator.

“The brief was to tell people about the works and closures on the Underground system and what we had to do is come up with concept that was easily recognisable, to show that they were spending money making system better,” said creative director Adrian Wheeler.

“What we did was we chose equipment that people use to make that stuff happen,” Wheeler said. Manual hoists are used for track replacement, he said.

Other images in the campaign include a powered screwdriver, jackhammer and paintbrush. Each Tube line has a colour; all four posters feature many of these.

The company also installed the hoist poster in long rows of poster holders next to the escalators. They used many different posters, the hook slightly higher in each, to give the illusion of the hook rising as one rides up the escalator. As commuters descend, the hook drops as well. “Because the ads are printed with an inkjet printer, it is very easy to print them quickly and cheaply,” Wheeler said.

Although the company bought a hoist from an industrial supplier, Wheeler did not know which, or the brand of the hoist. Can anyone identify it? Winners announced next month.