I bought a brand new CSI Airflow battery conditioner at the end of November to use on a tin top. I've had one of these on the Seven for the last 8 years after the previous battery went flat and couldn't be revived, and it always starts however long I've left it - and that battery is still going strong 8 years later.
However, I've found that the tin top draws 350mA all the time (the result of 2 immobilisers and an alarm) and the poor old CSI only puts out 300mA - so it's fighting a losing battle.
As recommended by Honest John - so it must be good.
Comes with crocodile clips and also ring terminals and a quick connector for permanent attachment to battery, plus instructions and the invoice I got with it - as here
Cost new was £39 + post.
It's literally run connected to the car for about 1 week, so I'm after £25 + £4 post (or you can collect from East Grinstead).
Cheers
Dave