A required tool for installation. The rubber mallet is necessary for all standard post cap and post call cap installation. Our metal caps are strong and heavy, however, if you attempt to hammer post caps onto the posts, it is possible to crack and/or break these metal, powder coated products. Always use a rubber mallet when installing our post caps and ball caps and gently tap center-straight down… and our caps will snap on to the top of each post. See Installation