The retail world is full of the remnants of brand fads that couldn't innovate and change. Once upon a time Girbaud Jeans and Hypercolor t-shirts couldn't stock shelves fast enough. My personal favorite, Zubaz, seemed to rule the world before their producer went bankrupt in 1996. So you would think shoemaker Crocs (Nasdaq: CROX) falls in the same category with its rubber shoe fad, right? Not so fast.

Beyond rubber
The problem for most brands is the inability to become more than a one-trick pony. I thought Crocs wouldn't be any different, fading into oblivion once dads were finally convinced by their kids that the shoes just weren't cool. But Crocs has moved beyond its staple product, adding sandals, shoes, boots and more to its arsenal.

Reliance on its classic models has gone from 62.2% of revenue in 2006 to just 11.9% in the most recent quarter as new products pick up the slack. New 2010 footwear accounted for an eye popping 23.7% of sales in Q2, showing Crocs has traction with its new products. And improvement has been broad-based, with new products driving revenue increases in wholesale, retail and Internet channels.

The question for Crocs is: how sustainable are these improvements? We've seen Heelys (Nasdaq: HLYS) go from boom to bust over the last few years because it turns out there's only a limited market for wheely shoes. But, maybe we are seeing another Skechers (NYSE: SKX), which seems to have a business of building fads.

Improvements at Crocs show a renewed ability to launch new products and give me hope for the company, but I'm still wary about the stock. In the shoe sector, Skechers has a better track record and better value with a 7.8 P/E ratio right now. Crocs isn't terribly overpriced at a 20.8 P/E, but if growth slows there is much more downside. I would rather be overprotective in the fashion fad business, even if Crocs has become more than just a rubber shoe.

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