This is what I stuck in:
http://www.tayna.co.uk/Type-076-Vart...ery-P3131.html
52Ah, 520CCA.
This was what I compared it to:
http://www.tayna.co.uk/Optima-Yellow-Top-P3118.html
38Ah, 460CCA
I can see the advantage of AGM type batteries, but not for this particular application. The car is a £600 banger, and a Varta Silver will do fine for what I use it for.