If your concern is with it rattling around under the seat I guess you could use some Velcro to secure it. You can buy some Velcro pads that are close in size to the unit. I thought about doing this but haven't.

You may say I'm a dreamer but I'm not the only one John Lennon Imagine Anyone who stops learning is old, whether at twenty or eighty, anyone who keeps learning stays young, the greatest thing in life is to keep your mind young. Henry Ford