The Viper Defender III Dartboard surround is the easiest way to get maximum coverage on your wall. The EVA Foam is 1? thick so you don't need to worry about darts penetrating through, but it's also light enough to easily hang on your wall without any extra support. Installation is incredibly easy, simply snap the segments together and place it onto your dartboard for 8.2 square feet of protection. To make things easy, this surround is compatible with both 18? and 17.75? regulation sisal dart boards. The included adhesive compression band can be used to ensure a tight fit on either sized dartboard so you don't need to worry about darts sliding by. Dartboard and darts are sold separately.