Here at Zacks, we focus on our proven ranking system, which places an emphasis on earnings estimates and estimate revisions, to find winning stocks. But we also understand that investors develop their own strategies, so we are constantly looking at the latest trends in value, growth, and momentum to find strong companies for our readers.Of these, perhaps no stock market trend is more popular than value investing, which is a strategy that has proven to be successful in all sorts of market environments. Value investors use tried-and-true metrics and fundamental analysis to find companies that they believe are undervalued at their current share price levels.On top of the Zacks Rank, investors can also look at our innovative Style Scores system to find stocks with specific traits. For example, value investors will want to focus on the "Value" category. Stocks with high Zacks Ranks and "A" grades for Value will be some of the highest-quality value stocks on the market today.One stock to keep an eye on is First American Financial (FAF). FAF is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock is trading with a P/E ratio of 10.23, which compares to its industry's average of 30.45. Over the past year, FAF's Forward P/E has been as high as 12.14 and as low as 8.57, with a median of 10.73.Value investors also love the P/S ratio, which is calculated by simply dividing a stock's price with the company's sales. This is a prefered metric because revenue can't really be manipulated, so sales are often a truer performance indicator. FAF has a P/S ratio of 0.96. This compares to its industry's average P/S of 1.03.Another great Insurance - Property and Casualty stock you could consider is Markel (MKL), which is a # 2 (Buy) stock with a Value Score of A.Furthermore, Markel holds a P/B ratio of 1.25 and its industry's price-to-book ratio is 1.36. MKL's P/B has been as high as 1.36, as low as 1.06, with a median of 1.28 over the past 12 months.These figures are just a handful of the metrics value investors tend to look at, but they help show that First American Financial and Markel are likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, FAF and MKL feels like a great value stock at the moment. Zacks Names "Single Best Pick to Double" From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all. As one investor put it, “curing and preventing hundreds of diseases…what should that market be worth?” This company could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in little more than 9 months and NVIDIA which boomed +175.9% in one year.Free: See Our Top Stock and 4 Runners Up >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report First American Financial Corporation (FAF): Free Stock Analysis Report Markel Corporation (MKL): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research