The lightweight Premium nosing boards have a smooth rounded edge. They are low-maintenance and easy to clean. They install easily with nosing clips screwed on the joist and with an invisible fastener joining them to regular boards. The 5.5 in nosing boards are perfect for a build-in seating or stair treads or for a nice deck frame. The PVC decking boards are splinter-free and are mould and moisture proof as they contain no wood.