Lenovo 0A33932 ThinkPad X220 Ultrabase & DVD Burner 45N7457 Laptop Dock The Lenovo 0A33932 ThinkPad X220 Ultrabase Laptop Dock offers great versatility in a compact, portable package! It supports Ultrabay Slim Blu-ray, CD-RW/DVD-ROM combo and Multi-Burner drives and is compatible with digital and analog video for outstanding connectivity. The integrated battery charger lets you keep a spare battery at the ready at all times while the streamlined design makes this dock perfect for use at home or on the go. Get the solution to your connection dilemma with the Lenovo 0A33932 ThinkPad X220 Ultrabase Laptop Dock! The included DVD Burner provides Dual-layer DVD-R technology provides the ability to record up to 8.5 GB of data on a single disc surface. This nearly doubles the standard DVD capacity of 4.7 GB. That means one side of a DVD-R disc will hold up to four hours of DVD quality video or 16 hours of VHS quality video. Dual-layer discs can also be read on DVD players that were originally designed for single-layer discs. In addition to its dual-layer DVD-R capabilities, this drive allows you to read and write to CD-R, CD-RW, DVD-R, DVD-RW, and DVD-RAM discs.