Sony HI-MD Minidisc: $7

Specifications:

• Type: 1 GB Hi-MD
• Recording time: Stores up to 45 hours* of music
• Diameter (Approx.): 2.55 in. (64.8mm)
* When recording in 48 kbps

Compatible Models:

MZ-NH1
MZ-NH600D
MZ-NHF800
MZ-NH900
MZ-NH3D