A range of vehicle accessories are produced or
described in non-metric units.
Tyres Diameters of
tyres are always gradated in inches and marked as such along the
As a result, tyre accessories such as
wheel trims are also inch-based. Halfords, for
instance, sells around twelve designs of wheels trim in diameters of 12", 13",
14" and 15". Only one trim design sold by Halfords is not in inches; this is a
diameter of 315mm (12.4").
Tyre Pressure The use
of pounds per square inch (PSI) shows no sign of receding. The use of the
metric "bar", while included on foot pumps dials and the like, is seldom
actually used by British vehicle users. Halfords produces an battery-powered
tyre inflator with the following statement on the outer packaging: "Inflates a
normal flat car tyre to 28 PSI in under 8 minutes". No reference to metric is
made. Halfords also produces digital display tyre pressure gauges, all of which
gives readings in PSI only. Only on a pencil tyre gauge does Halfords include
the pressure in bars.
Wiper blades These,
together with corresponding rubber wiper refills, are sold in intervals of one
inch. Due to EC directive 89/617, requiring the use of metric, most companies
now print the metric equivalent on packaging alongside the inches. However,
this has not undermined the use of the inch for practical
||Bosch uses a clever technique to bypass the EC directive altogether.
Bosch offers the product
description into two parts. To comply with EC law, the length of the blade
length is given with metric first, for instance, "400mm/16".
However, above the length is a large
number "16". This number is clearly intended by Bosch to refer to the length of
the blade. However, the 16 makes no reference to "inches"; it is presented
merely as a product number. Thus, to all intents and purposes, Bosch conveys
the length of the blade in inches as its most prominent indication, but remains
within the letter of EC law.