The present invention relates to a membrane wherein said membrane comprises a polymerized composition that comprised prior to polymerization at least one type of compound comprising at least 70 oxyethylene groups and at least two polymerizable groups. On the other surface of each of the substrates, a polarizer is provided. After the lay-up is cured and removed from a lay-up mold, leading edge strengthening ribs and a preformed composite nose skin are installed to complete the slat. The cache is further adapted to automatically determine when to send the request to the server over the network. The second groove extends into the rod from the outer surface of the rod toward the geometric center of the rod.