Off-peak cars are getting red hot. Fuelled by record sales, the number of these restricted-use vehicles - characterised by their white-on- red number plates - nearly doubled to 24,213 last year.

That is nearly 10 times the number just three years ago.

The spike in numbers is due largely to the relatively lower prices of cars, especially budget models, which are made even cheaper after the $17,000 tax break for off- peak cars.

First-time car-buyer Teo Chai Soon bought an off-peak China-made Chery QQ in November for $19,000, after subtracting the tax break. The minibus driver said: "The car is cheap, and is something I could afford.

"My wife is Malaysian, so a car is more convenient when we visit her folks," added the 40-year-old father of two young children.

Today, more than one in 20 cars on the road is an off-peak car. They can be driven before 7am and after 7pm on weekdays, after 3pm on Saturdays, and any time on Sundays and public holidays. Owners can use them outside the stipulated hours if they buy a $20 supplementary day licence.

Last year, 12,476 new off-peak cars were snapped up, a huge leap from 7,054 in 2005 - setting a new high for off-peak car sales for the fourth year running.

The bulk were budget cars, essentially because the $17,000 tax break works out to be a bigger percentage price cut on cheaper models.

But there were exceptions. Bigger and more expensive choices sold last year include the Toyota Fortuner (a seven-seat sports utility vehicle), the Lexus RX300, the Mazda MX5 (a sporty convertible) and even a Mercedes-Benz E200.

Businessman Victor Yong picked up a $112,000 off-peak Toyota Estima Aeras multi-purpose vehicle (MPV) last month. The non-off-peak counterpart would have cost $129,000.

"I have another car, a Nissan Cefiro. I have some extra money now, so I thought an MPV would be a convenient second car," said the 52-year-old.

Mr Vincent Ng, product manager at Honda agent Kah Motor, said: "Some customers find an off-peak car suits their working hours. For instance, there's a seamstress who bought an off-peak Odyssey. She takes her daughter to school in the morning and she goes to her shop right after that. She finishes after 7pm."

But by and large, budget models like Hyundai and Kia were still the most popular off-peak cars. Newcomer Chery from China was also a hot pick, with nearly half the 269 Cherys sold last year being off-peak cars.

Along with the popularity of off-peak cars, offences related to such cars have risen. Last year, they accounted for a record 894 bookings, mainly related to invalid supplementary day licences. There were 761 bookings in 2005 and 244 in 2004.

And with the number of off-peak vehicles doubled, observers reckon enforcement will be more challenging.