Movable number ring allows you to rotate the dartboard, allowing the fibers to heal, and extending its life; includes mounting hardware Viper Defender II Backboard & Sisal/Bristle Steel Tip Dartboard Bundle: Elite Set (Razorback Dartboard, Defender II Backboard, Edge Throw Line, 21st Pot with Darts Regulation Sisal Dartboard With Movable Number Ring Viper Razorback Sisal Dartboard, Metropolitan Cinnamon Cabinet, Shadow Dart Number Ring Viper Razorback Sisal Dartboard, Two Sets Starter Darts, Throw Line, Viper Defender · Manufacturer: Viper by GLD Products · Package Dimensions High resolution diamond markers, in doubles and triples, give the board a classy new look while giving you laser focus on hard to reach segments Viper Products: Elevate Your Gaming Experience – GLD Products Tournament quality regulation 18 inch diameter face, constructed from high grade self-healing compressed Sisal fibers