PFERD POLINOX Corrugated flap drum is Made from several strips of corrugated non-woven material, wrapped around a common core. The wavy structure of the non-woven fabric permits demolishing and matt finishing of surfaces without visible transitions. Ergonomically optimized products and power tools that contribute to greater safety and working comfort, and thus to health protection. Comfortable working with reduced vibration and lower noise. Specification: 4" Diameter. 4" Width, 5/8-11 Thread. 280 Grit. Recommended Speed RPM: 2,000 - 3700. Maximum rotational speed: 4800.