The slot on the left makes use of module key E, and the one on the proper uses module key B. The Wi-Fi card is keyed for slots A and E, so it suits in the left slot with no issues. Our Wi-Fi module is 16mm wide and 30mm lengthy, or 1630. https://products-dd.com/%E0%B9%81%E0%B8%AD%E0%B8%A3%E0%B9%8C/%E0%B9%81%E0%B8%AD%E0%B8%A3%E0%B9%8C-hisense-%E0%B8%94%E0%B8%B5%E0%B9%84%E0%B8%AB%E0%B8%A1-%E0%B8%A3%E0%B8%B5%E0%B8%A7%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B9%89%E0%B8%AD%E0%B8%94%E0%B8%B5-%E0%B8%82/