Pandrol is a British company, established in 1937, which manufactures clips used on rail tracks. Pandrol now has manufacturing plants in 12 countries. Over 240 railway systems in 91 countries have adopted its products.

In the olden days wooden packers were used to hold the steel rails snugly into jaw points mounted on wooden sleepers. The timber would allow for a little movement and would assist fish-plates to some degree in doing their job to allow expansion and contraction as was necessary with the steel during temperature variations. The words "saboteur" and "sabotage" are derived from "sabots" from the French "wooden shoes" (like clogs). When it was required to disrupt traffic on the railways one would knock the wooden blocks out which held the rails in place, an act of terrorism which, if the train driver didn't notice, would consequently result in derailment.

Paul Labiche, a French railway inspector played by Burt Lancaster, demonstrates to good effect in the 1964 film "The Train" The_Train when he prevents a German officer from removing a load of stolen works of art from France. The film is not all true. But why ruin a good story and great movie with fact?