 In 1959, the Memovox Deep Sea was equipped with a specific alarm to remind divers to begin their ascension, and in 1965, the Memovox Polaris was released with a patented triple case back to optimise the transmission of sound under water.The latter model would go on to inspire the current Master Compressor and AMVOX lines.It was reproduced in 2008 under the name Memovox Tribute to Polaris.