This is an R48G model laser lens optical pickup for a Sega Dreamcast. Is it a brand new replacement part. If your dreamcast is failing to read games, this will usually be the cause however there can be other reasons. This part is specifically for the Samsung GD-Rom drive not the Yamaha variant so this part will not work with the Yamaha drive (The Yamaha is more uncommon so chances are you will have the Samsung version). I have i have used one of these on one of my own consoles and straight after fitting it loaded up every game i tried first time. The way you can tell is if you open your console it will be stamped on the bottom right corner of the disk drive if its a Samsung or a Yamaha.