Buy from Amazon.com : http://fave.co/1FUqXub

TDK D120 Dynamic Audio Cassette Tapes - 10 Pack

Product Description :
Normal bias recording tape is optimized for excellent voice recording for lectures classes and dictation
Low noise surface helps provide an excellent signal-noise ratio for high-quality playback performance
Each audio cassette has a 120 minute total recording capacity or up to 60 minutes per side