The Mastervolt 62000550 AGM 12/55 Group 24 is a 12V, 55Ah sealed Absorbed Glass Mat (AGM) marine battery engineered to serve dual roles as both a starter battery and a service (deep cycle) battery. With a 400A CCA (SAE) rating, it delivers the powerful cold-cranking performance needed for engine starting, side thrusters, and windlasses, while its robust plate construction also supports medium cyclical loads such as onboard lighting, instrumentation, and entertainment systems.
In AGM batteries, the electrolyte — a mixture of water and sulfuric acid — is fully absorbed into layers of glass-fiber matting. This sealed, valve-regulated design means the battery is entirely maintenance-free, produces no gas under normal use, and eliminates the risk of acid spills or terminal corrosion. Because it requires no ventilation, it can be mounted in virtually any orientation or location aboard a vessel (except completely inverted).
Key Features:
- Dual Purpose: Functions as both a starter battery and a service/house battery in one unit
- 400A CCA (SAE): Excellent starting performance, even after extended periods of inactivity or winter storage
- 55Ah Capacity: 12V DC output with a maximum charge current of 15.3A
- Glass-Fiber Technology: Low internal resistance for fast discharge at high currents
- Thicker Plates: Extended lifespan and improved deep-discharge tolerance compared to standard AGM batteries
- Maintenance-Free: No water top-offs, no fumes, no ventilation requirements
- Low Self-Discharge: Approximately 3% per month — retains charge during off-season storage
- Universal Terminal Compatibility: Removable battery poles compatible with every standard battery terminal
- 3-Step Plus Charging Compatible: Works with Mastervolt and other quality multi-stage chargers
- Drop-In Upgrade: A direct replacement for flooded lead-acid batteries in Group 24 applications
- Two-Year Warranty
The Mastervolt AGM 12/55 is a proven, maintenance-free upgrade over conventional flooded lead-acid batteries. Its sealed construction, long service life, and flexible mounting options make it an ideal choice for marine, RV, and powersports applications where reliability and space efficiency matter.
