AGM Platinum Battery. If you're looking for a maintenance free and non-spillable battery for your bike, the Platinum AGM battery by BikeMaster® is for you. Manufactured from absorbed glass mat that captures electrolytes, these batteries have a longer storage life and higher performance than standard wet batteries. They are permanently sealed so that you do not need to check levels or add water. This battery by BikeMaster® comes with a one-year warranty. Features and Benefits: Longer service life. Resists sulfating. One-year manufacturer's warranty. Requires charging during prolonged storage periods (trickle charger sold separately). Greater cold-cranking amps. Detailed Specifications: Voltage: 12V. Size (mm): 135 Long x 89 Wide x 171 Height. Weight (pounds): N/A. Item Style: N/A. Amp Hour Capacity at 10 Hours: 13.