The Sanyo Micro Pack 35 case and controls were designed to resemble a film camera.
The unit was marketed for "capturing the first words of the child, terrorizing party guests and sending voice letters".
A push button on top of the player was in installed to override the conductive stripe and allow the cartridge to be played in the opposite direction.
[1] The high level of wow and flutter in the tape transport and the low frequency response made the device less useful for music.
[1] An unbranded version of the Sanyo Micro Pack 35 was briefly featured in the 1967–68 series of The Prisoner in the episode "The General".