SPECIAL editions tend to be used by car manufacturers as a means of spicing up a model range, adding a package of extras that collectively work out cheaper than if bought separately and generally offering buyers a bit more value.
They usually include things like a unique paint finish, upgraded sound system, sporty highlights like alloy wheels or more cabin comfort.
Well there's certainly a colour theme to Audi's special edition of the A3 hatchback - and it has nothing to do with paint and everything to do with the environment.
The car is a new 'green' version of Audi's 1.9 TDI turbodiesel, but with its engine, transmission and aerodynamics manipulated to reduce CO2 emissions to a lowly 119g/km.
And the good news for drivers of this model is that the cost of their road fund licence is a mere £35, handy given that the regular 1.9 TDI produces 135g/km and a substantially higher bill of £115 while a couple of the stable's more powerful 2.0 TDI units will land a VED tab of £140 and £165.
So it's a real clean machine, one that's also free from congestion charging for those who visit the capital. But how do they manage it?
Well without getting too immersed in techo-speak the engine uses components that minimise friction while the manual gearbox has ratios that favour economy.
In fact there's an in-dash indicator which informs the driver of the most effective gearchange points.
Add some aerodynamic refinements plus tyres with reduced rolling resistance and you have an upmarket executive hatchback capable of returning an average 62 miles per gallon.
You might expect the payback for this environmental consideration to be some lightweight punch. That's not the case - in fact the official performance figure of 0-62 in 11.4 seconds for this three-door hatchback barely does the car justice.
In time honoured Audi fashion the A3 is positive, refined and nimble to drive while the upmarket interior and excellent sound-proofing reflect the marque's quality.
There's plenty of space up front for driver and passengers and while the rear area may look cramped there's actually ample accommodation for two - even the front seat backs are discreetly scooped out for knees.
In fact the only criticism you could really fire at the car's interior is that the fascia - made of a rough-grain compound - is a bit bland, and the centre rear position is perched and uncomfortable.
Access to the rear is also easy - just a case of pull and slide - and there's reasonable practicality thanks to the likes of four door bins, central container with sliding top and cupholder, glovebox, coin slot and rear cubby.
Of course speccing up the car from Audi's extensive options bins can hike up the price. The test car featured Vienna leather upholstery at £1,270, a BOSE sound system costing £440 and heated front seats at £250.
But the standard equipment is extensive and includes front, side and head airbags, remote central locking, electric front windows, adjustable steering, ISOFIX child seat fittings, alarm, immobiliser and ABS.
FAST FACTS
Audi A3 1.9 TDI Special Edition
Price: £16,760
Mechanical: 105PS, 1,896cc 4cyl diesel engine driving front wheels via 5spd manual gearbox
Max speed: 120mph
0-62mph: 11.4 secs
Combined mpg: 62.7
Insurance group: 10
CO2 emissions: 119g/km
BiK rating: 18%
Warranty: 3yrs/ 60,000 miles, 3yrs paint, 12yrs anti-rust