What I don't understand is why the dimensions for some things are specified as a combination of imperial and metric units.
Two examples, which spring to mind:
Tyres: 17" diameter with a width of 225mm
Timber: 2" x 1" X-section and 3000mm long
wtf.
Why don't they just convert the whole lot to metric and round it to the nearest 5mm. In the timber example I gave above, it would be near-as-dammit 50mm x 25mm X-section by 3000mm long.
The tyre example:
13" Tyre ~= 330mm
14" Tyre ~= 355mm
15" Tyre ~= 380mm
16" Tyre ~= 405mm
17" Tyre ~= 430mm
etc.
It would make my life so much easier (I work in the construction industry), since I've always been taught how to use metric units. I know how to convert between imperial and metric (25.4mm = 1" and 12" = 1') but its laborious.
Also in the UK, it seems that EU law is deliberately trying to phase out the use of imperial units (remember a couple of years ago when grocers, butchers, shops etc. were forced to have all weights shown in g and kg as well as lb).