When we last discussed MK3 batteries in this forum (last year?) I recommended the Yuasa YTX20CH-BS because of its power specs (18 A-H and 270 CCA) and its size (its 6 x 3-7/19 x 6-3/8 inch dimensions just fit in the Mk3 battery cradle). At the time there was discussion over whether this battery utilized flooded or AGM technology; the acid is always shipped in a separate container and added by the customer. This product is now unambiguously described by the manufactuter and retailers as AGM. Technology has moved on since I installed this battery in my Mk3 three years ago, but I would NOT install a battery in a Mk3 that did not meet or exceed the 18 A-H, 270 CCA power specs of the Yuasa. Don't forget the Comeau starter, 3-phase alternator system, 6-gauge wiring, and a new sprag and both mating parts; the Mk3 needs all of it for reliable starting.