Post Post - how often have you driven past a post box in the middle of nowhere and thought that would be a good place for a cache?
If you wish to add to post post just remember to add the post box number after Post Post.
A Post Post should be cache and dash and depending on the site of the post box accessible for all.
This one on the A343 at Hollington Cross.
You are looking for a 5ml tube, tweezers may be usful and you will need to bring your own pen.