TODAY shoppers will be clamouring online and in stores for pre-Christmas bargains during the Black Friday sale.

However, there is that old school rule to question things that may be too cheap as, often, they can be too good to be true.

Conscious of the escalating cost of Christmas, and the amount of gifts we buy for family and friends, it is human nature to check out the cheapest deals to avoid busting the budget, but experts are warning us to be mindful that not everything we see is what it appears to be.

The charity Electrical Safety First said its own investigation had found highly sophisticated, dangerous counterfeits for sale through online marketplaces which were not necessarily vetted by retailers.

Its figures suggested that more than one million people found they had bought a counterfeit last year, including fakes of popular items such as NutriBullets, GhD hair straighteners and Apple accessories.

It is warning bargain hunters to "shop smart" and said the number of reported counterfeit electrical items had grown by 12 per cent in the past year and were almost impossible to spot.

Typical tricks used to sell fake items included imagery taken from official product sites, fake official safety marks and believable pricing, with some counterfeits costing just a few pounds less than the recommended retail price to avoid arousing suspicion.

The best way to guarantee an item's legitimacy was to buy directly from official online retailers, the charity said.

Tests carried out by Electrical Safety First found that while many items appeared sophisticated on the outside, even those with small fake internal components were at risk of exploding in up to 20 per cent of cases, leaving consumers open to serious injury or property damage.

Electrical Safety First spokeswoman, Emma Apter, said: "While the sales offer a great chance for shoppers to bag a bargain online, it's vital they keep their wits about them to make sure they're getting a real deal.

"Counterfeits are now readily available at the click of a button and despite fake electrical products appearing more convincing than ever, they can contain less than half the internal components required to run safely.

"We're urging people to shop smart. At best you could be swindled but at worst you could be putting your life at risk."

Linda Davis, West Yorkshire Trading Standards manager, also recommends shoppers to buy from reputable retailers whether shopping for deals online or on the high street.

For those shoppers who are searching for goods through online market places, Linda advises them to check the history and also where the stock is coming from.

"You can probably make a good assessment whether it is genuine or not," she explains.

She also advises shoppers to be mindful of the price too. While some fakes can be as expensive as the genuine product, generally if something appears to be too cheap it usually is too good to be true.

According to Linda there has also been evidence of counterfeits of popular brands including GhD hair straighteners; UGG boots, Michael Kors bags and MAC make-up appearing on social media, but the general rule for all shoppers is to be savvy and be aware of anything that appears to be too much of a bargain.

Originating in America, Black Friday is the day following Thanksgiving Day in the United States (the fourth Thursday of November). Traditionally it is the start of the Christmas shopping season in the States when most major retailers open very early, often overnight, and offer promotional sales.

Due to increased consumer awareness of discounting retailers around the pre-Christmas shopping dates, global information services company, Experian & IMRG, the UK's industry association for online retailers predict this retail season to rapidly surpass 2014. The main pre-Christmas shopping days which will prompt the rise in spending are Black Friday, Cyber Monday (November 30) and Manic Monday (December 7). Boxing Day and New Year's Day are also expected to see large increases in spend compared to 2014.

Martin Lewis, founder of MoneySavingExpert.com, has warned that the majority of Black Friday deals "aren't special" and advised shoppers to cross-check deals with items they actually need.

He said: "Above all, remember, if you don't want something, don't need it or can't afford it, then don't buy it."

And Which? urged shoppers to be prepared by registering for alerts from favourite retailers, searching for regular prices ahead of time in order to spot genuine bargains and to be aware that many deals are already available online.

It also warned that many websites slowed to a crawl last year, and suggested consumers register for online accounts early to "get in and out as quickly as possible".