This is a brand new/never used Apple Internal Laptop Hard Drive. It is a 2.5 inch/12.5mm - 500MB drive. IBM Model: DBOA-2540. Apple part number: 655-0259-A. This is inventory from one of the first Apple resellers called Sun Remarketing. 

The serial number of the one you receive might be different than the one in the picture. Ships in an anti static bag. 

Please see my other auctions for more vintage Apple treasures!