2004-2007 Buick Rainier SUVs used keyless entry systems that had either a 3-button or 4-button remote with FCC ID MYT3X6898B.
This vehicle also had seat memory as optional equipment. Seat memory keyfobs have a fob number embossed on the back of the case to make it easier to distinguish between two remotes used with the same vehicle. Internally, though, these fobs are identical, so it does not matter whether or not there is a fob number on the case.
Remotes Unlimited has the 3-button version on sale now for a very good price. If you have a 2004, 2005, 2006 or 2007 Buick Rainier, follow this link to buy a replacement keyfob at a great price.
These remotes are new and user programmable for all applications. You get instructions for self-programming plus free technical support. What more can you want?