What do I paint exterior timber with?

I have new timber railings and posts outside and want to paint them. What would you recommend?

We would recommend British Paints 4 Seasons. Lightly sand the timber first then apply one coat of British Paints PREP 4 in 1 Water Based. Allow to dry for a further 2 hours, lightly sand, and then apply two coats of British Paints 4 Seasons.