This is a refurbished drive for PS3, fully working with laser.
Before buying please check which Laser is in your PS3. The KEM450 Drive is usually in PS3 Slim with 120 or 250 GB. The 160 and 320GB Versions need other drives.
Please note that in most cases you don´t need to exchange the whole drive, mostly just the laser needs to be exchanged. The drive you should only change if your drive is mechanical damaged. But you cannot just exchange the drive. On the drive board there is an IC called "SPANSION CHIP". This chip keeps a special code which is only valid for the PS3 in which it was build in the first time. So you need to exchange the whole drive board, or if this is damaged exchange the SPANSION CHIP (good soldering skills are needed).