The VPI Stainless Steel Outer Periphery Ring Clamp fits all current VPI large diameter platters. This includes Classic 1-3, Scout II, Scoutmaster 1-2, TNT & HRX Series Turntables Only! The VPI Stainless Steel Outer Periphery Ring Clamp from VPI! First introduced on the HR-X, the Outer Periphery Ring Clamp centers on the platter, not the record, to provide vacuum-like hold down without the problems inherent in a vacuum system.Helps resolve the problems of tracking warped records. The VPI Stainless Steel Outer Periphery Ring Clamp only extends your platter's diameter 3/4 Inches!