When Nissan introduced push-button start as an option on many of its vehicles mid-way through the last decade, it chose a sleek oval design for the system’s factory keyless entry remote transmitter. One example of this style is Remotes Unlimited part 085-6249, shown at this link: http://www.remotesunlimited.com/catalog/product_info.php?products_id=1266.
Nissan has since released numerous remotes for both Nissan and Infiniti vehicles that utilize this same basic look. However, do not assume that these keyfobs are interchangeable simply because they look similar. Many of them are not. In fact, Nissan has employed more than one transmission frequency for these Smart Key remotes. So, when you are buying a replacement remote for your vehicle, be sure to use a reputable source and search by the Nissan or Infiniti part number or by the make, model and year of your vehicle to be sure you have the correct replacement remote.