Originally Posted by Epstein

That's when I found the Magna Power EXT18L, which IS the same as the Deka part that people are flocking to. The local Advance Auto Parts carries these (check website for availability by location). The local Advance also has these on sale. For $24.15. The cashier said that it looks like it's on clearance. Go buy now! Recap: EXT18L is $24 at Advance and weight 18lbs. A normal Group 35 battery is $50 and 34lbs. This is a 340CCA sealed AGM battery. Edit: for those averse to tiny batteries and want to quote me the huge CCAs of their man-batteries, the stock Miata battery in in the 300-340CCA range (depending on model).