A spiral wound band is a tube of abrasive cloth. It is made by first winding a strip of non-abrasive cotton cloth (also known as drill cloth) along a slick cylinder in one direction, and adhering it to a strip of abrasive cloth wound in the opposite direction. The net effect is an abrasive cloth tube with two layers of backing material. Smaller sizes are typically placed onto a rubber expanding drum and run at a high speed air tool. Larger diameters may be used on belt sanders and pedestal grinders, or spindle sanders. Spiral Wound Bands Click for Product Info on Rubber Expanding Drums. Spiral Wound Bands Sizes Diameters:   1/4", 5/16", 3/8", 1/2", 5/8", 7/8", 1", 1-1/4", 1-1/2", 1-3/4", 2",   2-1/4", 2-3/8", 2-1/2", 3", 4" Widths:   Any size from 1/4" to 36"   Common widths (depending on diameter)     1/4", 1/2", 3/4", 1", 1-1/2", 2", 3", 4", 5", 6" Material Specifications: Aluminum Oxide Resin Bond (most commonly ordered)   Grits Available:     400, 320, 240, 220, 180, 150, 120, 100, 80, 60, 50, 40, 36, 24 Silicon Carbide Resin Bond   Grits Available:     120,100,80,60,50 Zirconia Alumina   Grits Available:     80, 60, 50, 40, 36, 24 Other materials and grits may be available on request. Recommended Maximum RPM Usage: Diameters: 1/4" to 1"     Under 2" Wide - 19,000 RPMs     2" Wide and Over - 10,000 RPMs Diameters: 1-1/4" to 1-3/4"     Under 2" Wide - 15,000 RPM     2" Wide and Over - 6,000 RPMs Diameters: 2" to 2-1/4"     Under 2" Wide - 12,000 RPMs     2" Wide and Over - 4,500 RPMs Diameters: 2-3/8" to 3"     Under 2" Wide - 10,000 RPMs     2" Wide and Over - 3,600 RPMs Diameter: 4"     Under 2" Wide - 9,000 RPMs     2" Wide and Over - 3,600 RPMs Size & Grit Compatibility Issues Due to the thickness and inflexibility of the material in coarser grits, some small diameter bands cannot be made in coarser grits. Grit availability for bands based on flexibility issues are as follows: Diameters: 1/4" to 5/16"     Grit Range: 60 & Finer Diameters: 3/8" to 5/8"     Grit Range: 40 & Finer Diameters: 3/4" and larger     Grit Range: Any Grit