The proven Zacks Rank system focuses on earnings estimates and estimate revisions to find winning stocks. Nevertheless, we know that our readers all have their own perspectives, so we are always looking at the latest trends in value, growth, and momentum to find strong picks.Of these, value investing is easily one of the most popular ways to find great stocks in any market environment. 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 company value investors might notice is Customers Bancorp (CUBI). CUBI is currently holding a Zacks Rank of #1 (Strong Buy) and a Value grade of A. The stock is trading with P/E ratio of 6.67 right now. For comparison, its industry sports an average P/E of 12.68. Over the past year, CUBI's Forward P/E has been as high as 7.10 and as low as 3.57, with a median of 4.75.Another notable valuation metric for CUBI is its P/B ratio of 1.43. The P/B is a method of comparing a stock's market value to its book value, which is defined as total assets minus total liabilities. CUBI's current P/B looks attractive when compared to its industry's average P/B of 1.89. Within the past 52 weeks, CUBI's P/B has been as high as 1.44 and as low as 0.41, with a median of 0.67.Value investors also use the P/S ratio. The P/S ratio is is calculated as price divided by sales. Some people prefer this metric because sales are harder to manipulate on an income statement. This means it could be a truer performance indicator. CUBI has a P/S ratio of 2.02. This compares to its industry's average P/S of 3.05.Finally, investors will want to recognize that CUBI has a P/CF ratio of 7.26. This figure highlights a company's operating cash flow and can be used to find firms that are undervalued when considering their impressive cash outlook. This company's current P/CF looks solid when compared to its industry's average P/CF of 16.19. Over the past year, CUBI's P/CF has been as high as 7.30 and as low as 2.69, with a median of 4.27.These are just a handful of the figures considered in Customers Bancorp's great Value grade. Still, they help show that the stock is likely being undervalued at the moment. Add this to the strength of its earnings outlook, and we can clearly see that CUBI is an impressive value stock right now.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 Customers Bancorp, Inc (CUBI): Free Stock Analysis Report To read this article on Zacks.com click here.