Post caps and Finials serve two very important functions; one decorative and the other vital to the health of your deck and fence posts. Most people use a post cap for its ability to decorate and finish off a fence or deck post in style or with a theme. Some of the more beautiful deck caps are copper topped post caps and the Redwood and Western Red Cedar caps that can be painted or sealed and make wonderful statements.
Of course, there is a much more important reason tom use a cap or finial to top off your posts. They protect the posts from insect infestation as well as water damage that can easily get into grain of the wood through the top of an unprotected post. Using fence post caps is just the smart thing to do and if you have a great selection at really great prices, it's hard to turn that down.