It is a heavy-duty flexible hose for compressed air - workshop air lines, tool feeds, tyre inflation, construction and site air. The construction is a PVC and liquid rubber blended inner tube with triple polyester yarn reinforcement and a matching outer, which gives it the pressure rating and the flexibility to be dragged around a workshop floor without kinking or cracking.

Internal diameters from 6mm to 19mm, cut to order from 1 metre up to a 60 metre full coil. 6mm and 8mm suit hand tools and tyre lines; 10mm and 13mm are the usual choice for a main workshop run or for tools with a high air demand; 19mm is for high-volume kit and long runs where you cannot afford the pressure drop.

Yes, significantly. Air tools are rated at a given pressure and flow at the tool, not at the compressor. Too narrow a hose, or too long a run of it, causes a pressure drop that leaves an impact gun feeling gutless even though the gauge at the compressor looks fine. If a tool underperforms on a long line, go up a hose size before you blame the compressor.

It is manufactured to BS5118/2 and conforms to ISO 5774:2016. Those standards cover the construction, pressure rating and burst safety margin for rubber compressed-air hose, which matters because compressed air stores far more energy than water - a hose that fails under air pressure fails abruptly. Buying to a recognised standard is not a detail worth economising on.

It is an identification marking so an air line can be told apart at a glance from other hoses on a site or in a workshop. It is purely for identification and does not indicate a different specification. Many workshops find it useful when several hoses of similar size are run alongside each other.

Cut the hose square with a sharp blade or hose cutter, push the fitting fully home onto the shank, and secure with a hose clip - or a proper crimped ferrule for a permanent installation. Two clips at right angles give a better grip on the larger diameters. Never rely on a push fit alone: an unclipped air line under pressure can whip and cause serious injury.