power battery

Hi, if it were simple to do I'd be interested in being able to run my guitar amp from my battery. But just have a few questions is all that i hope you guys will know more than I do. Its a 15W amp but it says on the back that it needs a supply of 240V 75W. Is this something that the standard...

This weekend, for the second time in a year, I started my van after a few days camping to find the battery dead. I want to prevent this from happening again - it's too easy to get stranded. I've done a bit of research and found this: http://www.noflatbatteries.com/shop.html Has anyone tried...