Engine size,petrol or diesel?It is ok to go the same or higher on the Ah or cca as long as the battery fits the tray and hold down bracket.A replacement battery may not be the exact same dimensions.

I agree with the above (1st reply) the battery MUST fit the tray compartment, the fittings which hold it dowm must be the same type & the terminal connections must be the in the same positions and same shape (eg square or round)

The replacement battery can be slightly narrower or slight shorter in height, but the performance of the battery is what is important.

Have a look at www.performancebatteries.co.uk of Tewsbury, they provide an excellent service and deliver within 24 hours ( except weekends).

They also give free advice over the phone, they have a web based tool which recommends several battery types for any make/model of car and gives detailed dimensions/photos.. so you can compare with your exsisting old battery

(before you buy)

Furthermore they have a short video on how to change a battery,

all you need is common sense plus

1.the correct battery, 2.the radio code.3 a few spanners 4.daylight

Personally I have purchased two batterys within the last 18 months from the above

I paid £55 inclusive ( instead of £110 at the High street retailer) and £35 instead

of £45 at the same retailer.

ps PB also price match

(you have to ask and tell them what price you have seen elsewhere)

quick look indicates a battery for a A156 petrol, 1.8. 2005 is £46.(all in)