Made from flexible gasket material with resistance to heat and cold. Printed with a scale in inches, inch chart, tangent chart, and other useful markings. Economical tool for marking straight lines around pipe or for use as a straight edge. Pipe Diameter: 3" to 6." 1 Unit/Case; Gray; Size: 3.88" to 4. For nearly a century, professional workers in all walks of life have demanded Jackson Safety for their welding and personal protective equipment needs. The reason is simple. When it comes to providing innovative safety solutions, unparalleled features, long-lasting value, and comfort, Jackson Safety has set the standard.