In this segment from Wednesday's Investor Beat, Motley Fool analyst Matt Argersinger tells investors why Markel (NYSE:MKL) is a stock he's got his eye on at the moment. The stock continues to hit new all-time highs, having just broken the $600 mark for the first time. And with insurance stocks still being one of the few places left on the market to find undervalued stocks, and Markel still trading at less than 1.3 times book value, Matt still sees a lot of value with this stock.