Standard Diameter Masts (SDM's), are the most common diameter masts in the windsurfing industry. We offer SDM masts from PowerEx, GT, Neil Pryde, Severne, Maui Sails, Chinook and Epic. They have an inner diameter of 1.9" (48mm), require use of standard diameter extension, are 2-piece masts and available in 340 - 520 cm lengths. SDM masts come in 2 construction types: Epoxy or Carbon. Epoxy will favor entry level and recreational sailors who appreciate a price point mast that is durable. Carbon masts are available in 40-100% carbon options. The higher the carbon content equals lighter, more responsive mast & rig performance.