Is the MP5+ Stereo an upgrade from the AQ-IP-3B ? Aquatic AV July 16, 2020 19:59 Updated Yes! They're the same DIN size as well. Related articles Which wiring harness can I utilize to connect to the MP5+ Stereo ? MP5+ Stereo (MP521) - Owners Manual Can I install the marine model stereo into my Harley Davidson motorcycle ? MP6 (MP611) Owner's Manual How do I adjust my Day/Night mode ? Comments 0 comments Article is closed for comments.