Thanks Gareth. The reason I posted this question was because the reply from Tayna was very non-committal putting the onus onto myself to make the correct selection,,,
Earlier I found a useful tool on the Varta website (my existing battery is Varta); it lets you search for the current equivalent of an older Varta model that I shall order from Tayna taking your advice not to buy the cheapest.
Regards
Johnno