If you're experiencing déjà vu this Black Friday, there's a reason: Retailers are repeating products and prices from last year.

A whopping 93% of stores surveyed are offering customers year-old products for the same "discount" that was offered last year, according to a recent study from NerdWallet. While that may not be a huge issue for things like furniture and cookware, it does matter when it comes to tech and electronics that can be outdated or of poorer quality.

"It's probably not worth waking up very early for," said Matthew Ong, an analyst at NerdWallet.

Related: Shoppers not feeling Black Friday this year

It's not just the repeats that customers should be watching out for. Ong said that major retailers, like Walmart (WMT) and Target, (TGT) have special products, like TVs or other electronics, manufactured especially for Black Friday. The prices are great, but the items are of lower quality.

"If you're fine buying a TV that won't last until next year's Black Friday, I guess that's ok," Ong said.

The study analyzed 27 Black Friday advertisements, and found that 25 retailers listed at least one product for the same price in 2014 as in 2013. Office Depot (ODP), for example, offered the same wireless laser printer this year and last year, at the same $349.97 price point. Target, Walgreens (WAG) and PetSmart (PETM) also made the list of repeat offenders, along with many others.

The study also found that Black Friday discounts are offered at the exact same price at other times throughout the year.

Related: Deal or no deal? The Black Friday quiz

So how do you land the best Black Friday deals?

The way to be smart about shopping, Ong said, is to do the homework -- research deals and be strategic before the day arrives.

He said that good deals or specials can be found on Twitter or Facebook, as retailers push for engagement and try to be a shopper's first choice for Black Friday deal hunting.

"Stores are going to be crazy," Ong said. "Make sure you have self control, and plan ahead to make sure you don't overspend."