Batts Series/parallel?

[Balders]

Ii was certainly wary of the costs of going electric before I bought my 600 (ie packs costing well over £150 in some cases) but then when I ordered 2 packs from the .DE site, I ordered another two a couple of weeks later. I've got 6 good packs and two which are "ok" so 8 packs keeps me going in a good session (ie until the wife gets bored).