Mcgraw Hill W9 Portable Info

For maximum longevity, do not leave the speaker at 0% charge for extended periods.

Most portable recorders of the era used a single, cheap AC synchronous motor with belts that stretched. The W9 used : mcgraw hill w9 portable

Use the W9 to play audio versions of downloaded chapters or textbooks from your iOS or Android device. McGraw Hill Connect For maximum longevity, do not leave the speaker