Amazon is offering the PNY StorEDGE MacBook flash memory expansion in 64GB/128GB flavors for $39.99 and $94.29 with free shipping. The 64GB deal matches its all-time low, but the 128GB is a new low by $3.

These cards are designed to live inside a MacBook Air/Pro or Retina and provide a handy additional 128GB or 64GB of space. The shortened size means they sit nearly flush with the sides of the MacBook and won’t protrude out. Rated 3.5 stars. (via Giz)