One of the key elements of e-commerce systems is the online product catalog. In this paper, we discuss the interface of online product catalogs, focusing on its ability to help shoppers navigate and analyze product information. Specifically, we present a new interactive interface for online product catalogs that is effective in navigating through the product information space and analytically selecting suitable products. It uses a multi-dimensional visualization mechanism based on parallel coordinates and augmented by a number of visual facilities for filtering, color-coding, and dynamic querying. We present a prototype and explain how the prototype visualizes the entire product information space in a single page and supports intuitive exploratory analysis with the visual facilities.