If you’re scared of heights, this video of workers assembling a soaring tower in West Yorkshire, England, may make you a little queasy.

In the video, daredevil workers can be seen working at dizzying heights to construct a temporary 1,040-foot (317-meter) transmitter tower next to the 1,084-foot (330-meter) Emley Moor tower.

A Super Puma helicopter is used as a crane to carry sections of the tower to the brave workers who lean off the mast while fastened to a harness to reach the pieces.

The tower “will be used to transmit TV signals while work is carried out on the existing transmitter,” according to the BBC.