Diono Rainier Convertible Plus Booster Seat For $146.99 Shipped From Amazon Select from Shadow and Graphite. This was selling for $294.98 last week and is now the lowest price ever from Amazon. It has very good 4.4 star ratings. -Steel frame gives unmatched protection and durability for a 12-year product life -12-position adjustable head support Want to continue reading this post? Click here!